The SQAm works well, sound is OK, mirror clack is louder than the moto whining, and the motor is nice not because of the motor itself, but it gives you a return mirror, screen blackout Time ist about half a second then...
Electric cable release is also a bit more flexible than the manual one of the SQA.

Frame rate by the way (with Alkalines) ist 5 pictures in 5 seconds, tested with a filmless 120 back paper of course...

I just got the S 8/500, when using this lens on a tripod (4 kg Camera monster then) the motor drive is quite convenient.