I realize this post has not seen any action for a few months, but the topic is always current.
One of the lesser known things advertised about dry suits is that the gaskets come in many sizes & should be sized accordingly for best fit.
Neck gaskets in particular are very important to have a proper fit; having a too-tight neck is not only uncomfortable, but downright dangerous.
Neoprene gaskets are best stretched, they will take on a permanent set.
Latex gaskets on the other hand, take on very little permanent set so in many cases it's necessary to trim them, especially when someone with a "no neck" build gets into one.
You *might* even want to replace the "standard" size Medium with a new size Large.