In terms of price, neoprene and coated nylon suits are the least expensive. Neoprene suits are normally 5-7mm and offer warmth even without additional insulation. They are also stretchy and allow a snugger and more streamlined fit than trilam shell suits.
On the negative side, they wear out quicker than most other suits, are bulky, slow to dry, and hard to repair. I spent hours trying to locate a fix a pinhole leak in my wife's neoprene suit. They also seem to require a bit more weight than the average shell suit, but are easy to put on if you are not wearing additional underwear underneath. My wife has worn both her neoprene suit as well as one of my trilams with heavy thinsulate underwear and she swears by her neoprene suit for warmth.
The coated nylon pack cloth suits should be avoided in my opinion. They are inexpensive and work well until the coating on the inside breaks down - then you can pretty much throw it away. They also tend to use lighter nylon cloth on the outside and lack durability and abrasion resistance. Other than a lack of longevity and durability, they function the same as a trilam shell suit.
Tri-laminate suits are next in terms of cost and are good all round suits. In the heavier weights 420 or higher, they are quite durable and I have never managed to put a whole in either of the trilams I own. Mine also have kevlar knee pads which takes the worry out of crawling around on the bottom. They pack in a small volume, dry fast and are fairly easy to repair.
On the negative side, there is no stretch to the material so they tend to be cut a little bulkier and will have a longer than normal torso to facilitate getting into the suit. The end result is a little more drag in the water than many neoprene suits.
Vulcanized rubber suits are next on the list in terms of cost. In my opinon a heavy weight vulvanized rubber is very durable and beats just about any other suit made in that regard. They offer some degree of stretch, dry very fast and can be repaired in minutes with a regular tire patch kit. They are also ideal for diving in contaminated wateras they are easy to rinse. So if you just gotta dive in the cooling pond for the neighborhood nuclear power plant, vulcanized rubber is the way to go.
The down side is that they are heavy and relatively expensive (at least in my neck of the woods) I have also not seen one with a self donning front zip and this is a disadvantage compared to other styles of suits that are available with either a self donning front zip or a less expensive across the shoulders zipper.
Crushed neoprene suits like the CF 200 offer some great overall capabilities. They have some stretch, can be cut a little slimmer, are durable and offer some inherent warmth (not much, but some) the down side is price, which tends to be a little much for my tastes.
In general, neoprene suits will come with neoprene neck and wrist seals while shell suits will have latex seals. In my opinion neoprene seals are harder to replace but hey are more durable in the first place.
Zippers are expensive to replace regardless of the suit, but in general you can replace a zipper in a neoprene suit yourself, while it is strictly a factory job for other types of suits.
I have found that zipper quality varies and in general bigger is better as far as the teeth used in the zipper are concerned. The zipper in my Diamond is the best I have ever seen while the one in my SP Cape Horn is only industry average and on par with the one in my wife's neoprene dry suit.
