It's hard to add to what's here, but I'll throw my $.02 in...
to me it feels like cheating.
I had a previous version superstar which I loved- I was pretty sure I was only going to upgrade when I wore it out. I love the hull speed, I could get good pop (especially with beach ball in the cockpit), short enough to throw ends in the shallow features around here, and awesome down river.
Then last year some yeasty douch nozzle stole it out of my back yard.
Being boatless was not an option, and being a total gear head I had check out the new ones- I looked at the specs, read some reviews, and got in on the first shipment CKS received at the end of july last year. bought it sight un-seen.
I couldn't believe the difference- it made pretty much everything easier. better pop, easier loops, quicker cartwheels, spins in nothing, and feels noticeably faster on a wave. I haven't done much down river with it yet, but it felt fine in watertown early this year.
I'd have to say if there was any compromise it would be in the downriver area, mostly because it's so retentive that it might be harder to punch through something of significant size. The increase in hull speed will probably make up for it, but it's just a feeling...
Just as everyone else has been saying- there's a reason you see so many people in them.