I don't know the answers to your questions there so I hope someone like methodical or
speedchaser will chime in.
I bet the internals,
Engine casings etc will be able to handle the extra vibration but I bet my rent money that Engine mounts will take a beating. I just replaced two Engine mounts on my brothers machine last week. This is the ported and piped Engine. It had a real bad vibration. I changed the counter balancer bearings because I saw flaking in the oil but when I took it apart the bearings looked ok. Then I saw the rear two Engine mounts ------ they were toast.
My money says the heavier wiseco's will take out mounts.
CO