I just came to washington and bought a Harvey's it did not leak, bought a self doning it did not leak neo seals. I now am diving a Twrex Harvey's dry also. I had several drysuits through the years and for some reason I never need to send my suit in, When I want a new one I give the old one away cause I never need a spare when its in getting fixed. The Twrex I bought 10 years ago about 2'500 dives on it, the self donning had at least 3,500 and stop diving it 2 years ago
Now I need no spare But I like to have a self donning for solo and back zip for when some one is around, although I can zip or unzip with bungie strap. Saying this I think I can almost do with out self donning.