I build my Roubo Bench out of imported (from Texas :-)) SYP a couple of years ago. It has been a great bench, if I ever build another it will be just a copy of this one. I might leave off the wagon vise, not because it doesn't work well but because I just don't use it much. Although it's not a hard install and I use it occasionally it would probably be included in the new build.
Must be a sign of OFD, I can't seem to get to the point. Gotta ramble around in my feeble brain first to get the process kickstarted.
Any way, the SYP was construction grade and still pretty wet when I started the build. I have expected it to move a bit and because I cleaned it off last night (first time in months you could see bench) I got the Winding Sticks, straight edge, and large square out this AM. The big sucker is still dead nuts flat and square with no wind. Just a few nicks and some stains to show for a couple of years hard use.