Some random thoughts ... from the perspective of someone who's been diving dry for a long time ...
- Proper fit is the most important feature in any drysuit. Regardless of whether it's trilam or neoprene, a suit that's too small will restrict your ability to move, and a suit that's too large will result in folds that trap air in places you don't want it. If you don't have an "off the rack" body, the extra money for a made to measure suit is a good investment.
- Proper choice of undergarment is important for warmth. Someone mentioned wearing street clothes or sweats ... I wouldn't recommend it, since those are generally made out of cotton, which will provide you no warmth if they get wet. Keep in mind that all drysuits will eventually become wetsuits ... then you get them fixed. A flood, even in relatively warm water, can be a chilly experience in the wrong undergarment. A good undergarment is designed to keep you warm even when wet. There are many choices in terms of weight, materials, and style. The one that's right for you will depend on what type of suit you've chosen and the temperature of the water you're diving in. There are other, less important factors such as price, body shape, personal preference ... but the overall consideration must be that it keep you warm when wet.
- Suit or BCD for buoyancy control is a chronic topic of contention. If you're properly weighted, it matters not that much ... but if you're overweighted, or carrying large or multiple tanks, it becomes more important to rely on your BCD for buoyancy control because you'll be entering the water overweighted and have to compensate for that during the early parts of the dive. The problem with a big air bubble in your suit is that it moves when you move, and you're constantly having to "balance" that air shift. BCDs provide a much smaller space for air to shift in. I recommend to my students to only put enough air in the suit to provide loft for the undergarment, and use the BCD for its intended purpose.
- Weights ... someone recommended an integrated BCD. That works. But consider why you're wearing weights ... it's to compensate for the inherent buoyancy of your exposure suit. In colder climes, that can be considerable. Now think about what would happen if you should ever have to remove your BCD underwater. Your weights are in the BCD ... making it negatively buoyant and therefore wants to sink. Your suit is inherently positively buoyant and therefore wants to float. If you are using an integrated BCD, get some practice removing and replacing it underwater in a pool or very shallow OW ... you have to always keep the BCD on top of you. Otherwise if it gets away from you the BCD sinks and you float ... and guess where your air supply is ... :shocked2:
- Zippers ... they're the most expensive replacement item on a drysuit, so take good care of it. If you're choosing a suit with a standard YKK zipper, that means regular cleaning and lubricating. If you're using one of the new TiZip's ... it's less of an issue, although you still need to lubricate the end of the zipper, where the "car" rests when it's closed, from time to time. Both of my current suits have the TiZip, and I'm pretty sold on it for convenience and durability. The other big advantage is that with a YKK zipper you really need to be careful not to damage the zipper by bending it too tight when packing the suit ... or by tossing something heavy on your suit when it's in the bag. The TiZip is far more forgiving, and doesn't seem to mind being bent as much.
- Seals ... neoprene, latex, or silicone. I don't have much experience with silicone seals. The biggest advantage to latex seals is that they're easier and cheaper to replace ... and whatever material you choose you WILL have to replace the seals at some point. People generally choose neoprene seals because they're more comfortable. But they do cost more to replace, and you generally can't do the work yourself.
- Boots ... built-in boots are convenient, but often don't offer as much support as rock boots worn over a neoprene sock built into the suit.
- Ankle weights ... useful in some cases, but way overused. Good technique usually makes them unnecessary. They can, however, make good trim weights.
- When considering whether to go neoprene or trilam consider that if you're planning to travel with your suit, a good lightweight trilam will serve you better ... neoprene suits are really heavy, and take a long time to dry out. Luggage restrictions being what they are, you DON'T want to be coming back from a trip packing a wet neo suit ... two or three trips will cost you more in overweight fees than you paid for the suit.
Just some thoughts to add to the mix ...
... Bob (Grateful Diver)
