I've done it. My main is about 9 months old, and just barely twangs the backstay on it's way by. I've noticed no wear patterns on the sail where it touches. Is that what you're concerned about?
As you commented on one of the other forums, the sail is bent enough in a breeze, that it doesn't actually touch the backstay. Mine only touches when the breeze is too light to bend the batten. In that case, I just hop on the transom and and "snap" the backstay and the sail slips through.
I did not require roller bearing cars, but my boat is only 25' so the sail is smaller than yours would be.
Unfortunately, I cannot provide you with any data on performance vs. the regular main because my original main was 40 years old, blown-out and very tired. I didn't sail with it long enough to make a valid comparison. The main is powerful, and I suspect that I'm reefing a bit earlier than with the normal main to reduce weather helm, but the reefed shape is wonderful and I get great speed and balance out of it with my 100% jib.
I guess the bottom line is: Don't make the extra roach so big that it's slapping the backstay, even in a breeze or you WILL experience chafe and that'll be expensive later on.
I'm not a sailmaker, and I didn't stay at a Holiday Inn Express last night, so my opinion is worth exactly what you paid for it.