All bikes have what I call mechanical clatter and I bought a vision after testing a harley ultra 103 ci. and some other bikes. I couldn't believe the shaking at idle the harley had and I expected it to smooth out at some stage in the rev range but it didn't enough to satisfy me.
As with all bikes it pays to check as many nuts and bolts yourself when you get it just in case one or two are loose and it helps get familiar with the new machine.
We went on the 1000 K trip from Melbourne to Sydney along with 60 other victory bikes and there was no mechanical problems or nothing rattled off on any bike as far as I know. All riders arrived in pretty good shape as well.
maybe this will tell you why harley rattles. I sold my new harley street glide with 2000 on it and bought a vision. Will never go back.
"Will never go back."
Lost count of how many times I've said that to friends.
Re-edit: Just realised the date of that above post, oh well.