There is no question that leather is a safer material in a crash than textile. If it weren't, you'd see people racing in textile suits. If you're planning on spending time at high speeds, especially on a track, you should consider a one-piece leather suit. Why one piece? Again, it's safer. You don't have that exposed midriff thing going on, and you'll know that every part of your body is covered, except that which will be under your helmet, boots, and gloves.
For everyday riding, textile is usually more practical for most people. It is easier to get into and out of. Many people find leather to be heavy and hot. But leather holds the armor in place better and will help preserve your skin when you go sliding at high speeds.
One of the problems with a one-piece suit is that you have to shrug out of the upper half when you want to go to the bathroom. This leads some people in the direction of a 2-piece, especially for touring. If you get one of these, make sure there is a 360-degree zipper between the pants and jacket, for added safety. That said, getting out of a one-piece isn't really hard if you're wearing appropriate underwear (see below).
Most serious tourers in this club have textile suits such as the Aerostich Roadcrafter. Most people who regularly head for the track have leather suits, although they often wear textile when touring or commuting.
You want leathers to be on the snug side (almost tight) so as they break in they fit to your body. They should be tight enough so that the armor will not move when you go down. Look at some of the pictures of the pro racers; theirs are TIGHT. You also want to account for room to allow a back protector. If you're looking for a one-piece, keep in mind that they may be manufactured based on seating position of the bike, meaning they may fit oddly while standing straight up. Find out how they feel when you're sitting on a bike.
Leathers may take a while to break in. If you have a reasonably average build you should be able to find some good-fitting "off the rack" leathers. If you have more cash (although not necessarily,see below) there are places that make custom leather suits. All brands fit differently and are sized a bit differently as well. Try them on, or plan on sending a few back until you get the right fit. Try on as many brands as you can to see which fit you best.
If you usually ride in hot weather, or are the kind of person who sweats all the time in the summer, you may want to get perforated leathers. These have tiny holes all over them to let air in while you're moving.
Plan on wearing either thin silk long underwear or some kind of space-age wicking material under the suit. Silk doesn't hold an odor like synthetics sometimes do, and it's a lot easier to clean silk or polyester than leather. Underwear helps make your leather suit easier to put on, take off, and keep clean. It also helps with body movement, as the leather won't be sticking to your skin.
Once you get a good-fitting set of leathers, you may not be able to get many warm clothes under them, but you can always wear warm stuff on the outside. It won't look quite as good, but would you rather be cool or freezing?
You don't necessarily have to clean your leathers, but you should invest in some Lexol leather conditioner. Lexol has been recommended as the best of its kind by seasoned riders. Conditioning will help break the suit in faster, and if you regularly use it you shouldn't have to use any kind of cleaner on it. There are good leather care tips on the Lexol site, in the auto and horsey sections.
Now go find some leathers, then get to a track for complete motorcycle satisfaction.
Getting out of leathers It's really not this hard; these guys would have an easier time of it if they had undersuits on.
Custom leathers for less
There is a new 'company' on the leathers scene that has aroused interest in the club. Actually, it's one motorcycle enthusiast who designs and sells suits in addition to his full-time job. Spartan Leathers are low-priced due to the lack of overhead, marketing costs, or fancy offices. The quality is very good, but don't just take our word for it. Google for reviews of this company; it's hard to find a bad word. Communication is topnotch, fast, and detailed.
Custom suits are of the most interest to people who are a little differently-sized from the norm, such as our model here. However, most riders could benefit from a suit that's made for them. Spartan helps you do the measuring to ensure a good fit, then they contract out the work to a factory in Pakistan (and if you think there's something wrong with that, take a look at the label in your current gear).
The suit lives up to its reviews; the leather is good quality, the stitching is very well done, and it has good venting. There is CE armor in the knees/shins, elbows/forearms and shoulders, with a fairly standard pad on the back, which you'll most likely want to replace with a back protector.
One thing to be wary of is that some shorter people have reported an issue with the knee/shin armor being too long, making it painful when wearing boots.
The suits come with a zip-out/removable mesh liner that's designed to protect the leather a little from your sweat and provide ease in doing repairs/alterations:
The double zips up front are for ease in getting the suit on/off. This is a recommended option.
The main seam is triple stitched. You only see two exposed because the third is hidden, and glued for strength.
The leather is supple right out of the box and is very comfortable to wear (unlike many off-the-rack suits) and will clearly provide very good protection. Note the perforations. You can specify as much perforated leather as you want.
Custom does mean patience. Lead time will vary depending on season and business levels. These took a little over three months from ordering to arrival. If you want to deal with a motorcycle enthusiast who's trying to grow a new business, and not some faceless company, you should consider Spartan Leathers.
Points to ponder
Observations by Bokonon
For being at a track, there is nothing better than a good leather suit. I don't think I like my leather suit on the street, though.
Before you plunk down the money necessary for all that dead cow, make sure you know what you're getting into. Try them on, walk around, sit on a bike if you can, and see how it feels. Leathers aren't usually required for track days (check), so you can probably go to one with regular gear. Ask the people there about their experiences with leathers, and try to get some advice. If a friend has a suit, pick it up and see how heavy it feels. Try it on, if possible (realizing that suits are often sweaty and stinky).
My suit fits me well. It tucks into boots and gloves very well, and the armour stays in place. However, fitting that well doesn't work for me on the street. It's harder to see everything that's going on, as I can't move as well as I can with textile gear, even with a silk undersuit on.
Leather is heavy. My suit tends to get pulled down from my shoulders by gravity. This makes it even tighter, and makes turning my head to check the lane behind me, or to see up the side street at an intersection, much more difficult than with a regular jacket and pants. Some people agree with this; others don't have this problem. It's probably exacerbated by my being middle-aged and the weather always being hot and sticky where I live.
You should also consider the kind of weather you usually ride in. The torso of my leathers is perforated, but the legs aren't, and after an hour my legs not only get hot, but the accordion bits behind the knees become uncomfortable. At the track, you usually stop and cool off at least once an hour. That might not be the best way to enjoy an afternoon on the backroads.
I'm keeping it for track days, though. Leather is more abrasion-resistant, and turning your head or otherwise swiveling your body isn't as important on a track. I don't have any problems moving side-to-side in my suit, which is where the majority of track movement is.
You have to wear what's comfortable for you, or you won't want to ride as much.