Has anyone purchased an AreoTrunk for their Sofrider? This is an areodynamic bag that fits onto the back of the seat and requires no other attachments. It is supposed to improve the performance of a recumbent bike. I was wondering if hanging the bag of the seat would unduly affect the bike balance and wheel slippage going up hills? Any advice or assistance on the best bags for touring would be appreciated. Don Brown, Sooke, BC Canada