Before I bought my dry suit I did about 2 months of research on them. I ended up going with a DUI CNse custom fit. I could not fit into any off the shelf sizing. There are a lot of factors to consider when you are buying a dry suit. One of the factors that I didn’t see mentioned was the added weight that you will have to carry if you decide to go with a neoprene based dry suit. I dive both wet and dry.
I dive a 7mm Pinnacle merino wool elastoprene suit hood boots and gloves and am able to get away with diving with 20lbs of weight. When I dive in my dry suit I end up having to carry 42lbs. Ya I know the first thing that everyone is going to say is that I have too much air in the suit, or the suit is too big. Not the case though. I got my measurements done by Faith from DUI at the beneath the sea in NJ. I can sink myself with 36-38lbs with no air in the suit. I ending up at the 42lbs allows me to add the air that I need to stay warm. For undergarments I wear a one piece fleece that fits snugly.
I had the opportunity to go to a DUI Dog Day Rally and tried a TLS450. I had to go with a suit that was a little bigger than the one that I dive for sizing reasons but I was able to sink with 26lbs and able to dive with 30lbs.
Don’t get me wrong I love my dry suit but make sure that you look at the type of diving that you are going to be doing. The neoprene is more abrasion resistant that the tri lam, but you pay for it in the amount of weight that you have to carry. If you are not going to be going in and out of wrecks or caves then you may not need the extra abrastion resistance of a neoprene suit.
I find my self diving more in my wet suit than dry because of all the extra weight that I have to carry. In all the questions that I asked and of all the people none of them brought this factor into the equasion for me.
Good luck on your search. Hope this helped.