I installed a Randallsrack and have been happy with it. Cant speak to any other R&P system tho. There is plenty of room for the headers. No interferance at all. I did a write up on some of the issues I ran into with the RR unit. It's about 5 or 6 posts before yours titled Randalls Rack review.

Good luck with your rack , the RR is definitely better than the old stock system. Nice tight steering now, no more slop.