Sorry I didn’t see this post earlier, but I will give you some reassurance.
I purchased an Amp dry suit in January and used it dozens of times through April. I have been extremely happy with it overall. Here are my observations and advice based on my use so far.
First, if you have not tried a dry suit previously, the most obvious thing you will notice is the neck gasket. For me, the Amp gasket is snug, but not uncomfortable and I am fairly sensitive to neck pressure. If you find the stock fit too tight, check the internet for instructions on trimming the gasket as it is cone shaped and trimming the end will result in a looser fit. Don’t go too far though as you do need it to stay tight to ensure it won’t leak.
The Amp itself feels quite sturdy and has nice reinforced patches at the knees, elbows and seat. You should lube the zippers immediately and then practice using the main zip (unless you will have a friend to help get it started from the back). With some practice, you can operate the zipper by yourself, but it is awkward at first as it starts behind your shoulder.
I found the Amp breathes pretty well, but it is heavier weight than some other suits, so it will be warmer than some of the more expensive suits. I believe the Amp uses more layers than some of the more expensive suits. As I mentioned this has good and bad points. I believe it is more robust than lighter suits and will need less insulation than lighter suits, but it will be warmer in hot weather. I have worn mine in temperatures up to about 60 degrees and I am generally comfortable (though at that temperature I’m just wearing shorts and a short sleeve rashguard under it).
Here are a few additional tips.
The Amp has built in socks. Like most, these are somewhat delicate. I always stand on a carpet or towel when getting into or out of the suit to ensure that I don’t tear or puncture the socks on sand, gravel, rocks, etc. I also suggest wearing a full neoprene boot over the socks.
Remember to ‘burp’ the suit. I forgot to do this the first time I tested the suit. When I jumped into the water, I looked like the Michelin Man because of all the air trapped in the suit that got pushed to the surface of the suit from being immersed in the water. To burp, when you are fully sealed in the suit, you just gently pull the neck gasket away from your neck and hold it so that it is not sealed against your neck. Then slowly do a full squat. Once you are in the full squat, release the neck gasket so it seals against your neck and stand up. The suit should suck in around your body.
Good luck and enjoy your new suit.