Hammer,
You heard the Bose in action at the Bosier City Jam. If you walked the room, you undoubtedly know the dispersion was excellent.
In your situation (back problems) you should know the Bose Model I or II is 4 pieces. The model I power stand (which house 3 amps)is 34 pounds. The Sub is about 28 pounds. The stacks, just 15 pounds each. A snap to set up and tear down. But,...still 4 pieces. No problem on a Rock'n Roller. Without a cart, that 34 pounds can feel like 50. The Model II has a slightly lighter power stand.
Take care of that back of yours.
Eddie