I've been riding the Fat Lady V1 and V2 for the last year and half. I originally replaced my 2010 16m Rebel with the Fat lady V1 after trying the Turbine, Dyno 16 & 18, Infinity V1 prototype(all 2011 models). I did not choose the Fat Lady V1 based solely on it's lowend. In fact, the Turbine, Dyno 18, and my Rebel had a touch more lowend than the Fal lady V1. I choose the Fat lady V1 because it was the most fun to fly out of the bunch. The Fat Lady felt more like a 13-14m kite with the lowend of a 16-17m kite. Just for the record, I weigh 200 lbs and ride the Fat lady with high volume surfboards(>34 lit.) in San Diego coastal conditions. For me, I don't bother riding unless it's over 9 knots since you can't really do anything with a surfboard in under 9, even 10 is a challenge with a descent size swell. Also, in light onshore wind, it's mainly upwind wave riding with some hacks and airs as you are riding out. When it jumps to 12-13 knots with more side-shore conditions, down-the-line wave riding is do-able on the Fat Lady. It turns faster than all the big kites I've tried and has good drifting abilties for such a large sail, maybe a combo of the low-aspect ratio of the kite coupled with the actual weight of the kite.
The new Fat Lady has more lowend the the V1. The turning seems a tad bit slower(still faster than your usual big kite) and a little less pivoty. . Also, the v1 had a little fluttering in the turn when you cranked it hard, where the V2 I haven't noticed. The kite also seems a little bigger than the first version and and a touch more of a higher aspect ratio. Hard to tell, but I will lay them on top of each other a snap a pic soon. All in all, I like the V2 better for overall performance. The V2 also looks a bit more durable than the v1 as evidenced in the bumbers on the leading edge and the neoprene covers over the strut clips.
I have been using a 23 inch Slingshot bar with 27m lines, the same bar that comes with the Turbine. Seems to work just fine.