The Karma doesn't make for a very good ski in the park, or for flat-land dicking around.
The Dogen is a fine soft ski for getting around the mountain. Don't expect to charge fast down the hill, but then you wouldn't do that on most any park ski. They're going to be too soft for that.
If you're mostly on hardpack, screwing around on the slopes, and hitting the park the Dogen is a pretty solid ski.
The Karma works much better as an all-mountain twin for skiing everywhere on the mountain and being able to hit kickers, but it's way too stiff and has a bit much swing weight to be used as a primarily freestyle ski... unless of course you live in the pipe
I just picked up a pair of last season's Scratch FS's which are pretty similar to this year's Sprayers and they're much more fun for just screwing around.
I use my Karmas on decent snow days when I'll be on the steeps, out in the trees, and running fresh tracks in the powder. I use the Scratch's for the sub-par days when I just troll around the mountain looking for jumps to hit and trees, etc. to jib.
-Nathan