After reading some of the mixed reviews on this thread on the seaskin undergarment fitment, I opted to just go for the base layers and I'm going to go for a couple of the more expensive insulation layers that it seems like most people end up with anyway. I'm thinking that a decent option might be to use the Seaskin base layer, and for 40-60 degree water go with something like a 1pc 4E Halo AR (yeah, like $700, yikes, glad I saved a bundle on the trilam!), and for like 60+ degree water go for like a top and bottom Waterproof Meshtec 3D set? Fit is still a big concern though, I have a longer torso and shorter legs. Do you take your best guess and order from an online shop that has a good return policy or take a (long) drive to a brick and morter that has some size options in stock?
Its a shame, if the undergarments sold by Seaskin turned out to be a better fit in the crotch area, getting them MTM would be the cat's (and diver's) pajamas.