I even 'hand wash' in my machine - on gentle. I've never had an issue.
Mum's spin them so much that if you don't get them out and hang them straight away the creases are so so so bad because they're almost dry from being spum so hard. I can't see that as a good thing for the elastic on my nappies. You have to untangle everything from everything else too cos it's spun so much it all gets tangled.
JMO though.