I paddled a 2007 superstar until this last summer when it broke, and got a 2010. They are different boats for sure, but at least for me the benefits of the 2010 outweigh any potential losses, especially the comfort of the 2010 (way more comfortable and ergonomic). Some people say the 2010 is slower--I didn't really find that to be the case. I paddled it in the biggest water of the season around here, and loved it. Stevens down on the poudre at close to 6 feet was great. The day I picked it up at CKS I went and surfed the the wave and the boat was simply much better than my 2007--faster, looser, and MUCH more comfortable. The water came up overnight, and my first down river run was on the Ark at around 3000 I think (railroad to town). I found the boat was great in the pushy water--really melted through features well. And actually, the shorter more bulbous stern made the unintentional squirt much more stable actually--my 2007, with the more slicey shape, would tend to cartwheel me off the stern if I got squirted. the 2010 just kind of holds you there in a much different way, which I found to be nice for recovering from the unintentional squirt. The boat boofs well too, and down river wave tricks are great. Love the boat, but also loved the 2007.
FYI, I run everything in my playboat up to big water class IV, and the occasional V or V-, just so you know where I'm coming from. I like the tiny boat in the big water though--less to get in the way. I save the creek boat mainly just for creeking.