Brad, I normally shoot all of my slide films a bit under rated, ISO 80 on Kodak E100VS, and the E100G and GX, which helps alot and on Fuji Films I shot Velvia at ISO 40 and Provia at ISO 80, the way to check on fuji, is check your shadows and if they have a bit of blue, then they have been underexposed a bit...

Good Luck, just remember to develop normally and you should do okay.

Dave