Since no one else replied . . . I bought a drysuit in March (also from DRIS) and have liked it a lot. If it is a membrane suit (bilam or trilam) the undergarment purchase is probably just as important as the drysuit purchase, which is something I didn't really think about at first. However, for my first several dives in roughly 43-46F water, I got by with Cabela's mid-weight long underwear and a random assortment of sweats. As everyone will tell you, cotton does not do well when wet. If everything stayed reasonably dry, the sweats worked alright, but not ideal. Make sure you figure out weighting in a relatively shallow and safe environment, since different undergarments can affect buoyancy a lot.
Anyway, we eventually bought the 4th element Arctic undergarments, and the 4th element vest (x-core) for really cold water. I , wear the Cabela's long underwear under the Arctics. Those have worked much better. I also think DRIS has some house brand undergarments that are a little cheaper and probably made out of similar material. SEAC has a cheap -- but very thin -- set of undergarments. Of course, if you are not diving really cold water, you might not need as much.
You might get more replies in the equipment section (exposure suits).