We've used them on and off over the last year - 18 months. Fairly fast turnaround, but we did seem to get more than our fair share of scratched and unplayable discs.
After cancelling late last year, they sent us a voucher for 90 days free subscription. Nearing the end of that soon and will probably cancel again, as although we're getting less scratched stuff, we're now approaching the point where there's not much left that we want to watch...
AC