I've got an '06 Shadow Spirit 1100 and love it. Got to have a sport-type bike also, but the Shadow is great. You can keep the 700 size Shadows, the 1100 is the smallest I'd have, and I would have had the VTX1800, but they don't make the Spirit style bigger than the 1100. I just took a trip to Cabela's a couple weeks ago, 2up down the interstate (combined rider weight of about 350lbs) 80-85mph the whole way there and back and got 47mpg. I don't even put it into 5th gear unless I'm cruising over 65. It's about as comfortable as my recliner and I can hold my own on the twisties with it (for a cruiser). I've gone thru a few bikes in the last few years and ended up with the two I have now (I'm kind of partial to Honda, I worked for them in another life). SUMO would be fun as hell, but less practical and more trouble than your R6. The trouble part is the only thing talking me out of getting one (I'm an old-school dirt rider)