Tri-radial is definitely nice, but unless I'm racing it's hard (for me) to justify the extra cost. I agree that cross-cut is the first to lose it's shape, but as a compromise between cost and performance, I think that it is a rational alternative. From what I've seen, most sailmakers specify some sort of laminate for their radials. For a cruising boat, I'd stay away from laminates unless the budget allows replacement within 5 years.
Either way, I'd stay away from mitre cut. BTW - Bi-radial should not be confused with a mitre cut. I have an old North bi-radial and while it was a great sail, I'm replacing it with a cross-cut.
Just my %0.02..... Sorry to stray away from the original question.