I have access to plenty of various sizes of vinyl tubing to protect the stays and mudguard rail, and based on the attachment method the RE bags would seem the way to go, since there'd be no scratching of the top.
For those longer trips a tank bag is definitely workable, and NFG carries a Tank Rack in Black or Chrome that attaches via suction cups. Seems like a really viable solution since they're "easy on...easy off" depending on the type of ride.
Still, other projects are a priority so I have plenty of time to mull it over.
helo