I've used the exporter with sketchup 8, which i still use.
I don't design anything, it's just for exporting warehouse models to X.
A few things to watch out for.
SU models often weren't designed for low poly game use, so check the poly count (5K to 25K) per model shouldn't be a problem for 3drad.
Another issue is flipped faces, this happens a lot, in SU you wont notice them, but in 3drad you will.
I blame SU for this issue.. in 3dsmax this can also happen if you manually create the faces, as the direction the poly faces depends on the direction/order the vertices are created, i assume this also applies in SU, but it's render engine is some how compensating for the flipped faces.