I think the "clanking jarring 500 body" and "big mirror slap" is more theoretical than actual, certainly at everything but maybe the slowest shutter speeds. You hear lots of talk about it but I have yet to see it demonstrated or noticed it in my pictures. If you are talking hand-held, operator induced vibration would likely cause a much larger problem, and tripod use with the mirror-up function is easy and will eliminate that possibility. But yes, all that's redundant with the SWC, one of the best cameras ever designed.