i've used replacement chainrings by Specialites TA rated for 9-10 speeds on my 8-speed rig and there don't seem to be any problems.
my reason for getting such a nice frame but keeping a old groupset is really down to cost. i can get the frame chep at my lbs where i work, and since i've already got a groupset, it'd be a nice way to save some money! plus, i like the retro look
