I have 315.35.17 BFG DR, which are mounted on 12" X 17" wheels from John at Complete Custom Wheel ( www.ccwheel.com ). I think the extra inch of width makes for a better contact patch. Lots of people in my area run his wheels and are very happy with them. Might want to do some searching in the tires and wheels board on the other forum.
But, in answer to your specific question, many C5 folks are running the ZR1 and the GS wheels with DR and the off-sets on both wheels are fine on a C5.