I just bought a 3mm Pinnacle Elastiprene. I had initially wanted the Seal for less compressibility or a Bare Velocity for price and supposed fit. Well, neither fit me well at all, and both were quite difficult to put on. The Elastiprene was much easier to don and fit me better, probably because of the extra stretch.
As for Pinnacle vs. Bare, to my eye the Pinnacle is better constructed. Whether that makes any difference in how it dives or how long it'll last I have no idea.
I looked at the Merino Elastiprene as well, but could get the regular Elastiprene at a very attractive price, and just couldn't justify the $200 or so price difference.
The Pinnacle neck closure bother me as well. But it's for warm water only, and if I leave the velcro closure open, it's ok. I guess it may get better with time.
Henrik