Michaelfahlund--that ski (do you mean MX 83?) will be fine, I'm sure, as long as you don't overdo the length of it. Especially if you intend to ski it mostly on groomed or firm snow, I expect you'll enjoy it most in a length about the same as your current skis--173cm. If you like "turny" skis, I'd even consider the 163cm model, with a 15.5m sidecut (according to the manufacturer). That's a slalom ski length, but not quite the tight-radius sidecut of a true slalom ski. The shorter length won't be quite as forgiving in the "occasional 3-4 inches of morning powder" you've described, and they will be more challenging especially in deep powder, but they'll be a lot of fun on the harder and groomed snow you've described. (And no matter what many will tell you, they will actually work well in a little powder and crud, at least if you ski them with skill and finesse.)
With a fine ski like these Kastles, I cannot highly enough recommend that you check them out first with the help and eye of a good instructor--particularly if you get them in the shorter lengths. They'll be unbelievably fun, IF you ski them like the fine and precise tools that they are. If you push them around the way so many skiers do, they won't work any better than any other ski, and may well not feel as "easy" to ski as your current skis.
To answer your original question--it's really not so much a question of skill level as of what you are trying to do with the skis at any level. Those skis are meant to slice and glide, to slide through the snow the direction they're pointed, rather than skidding and braking sideways, as a rule. Yes, they'll work as brakes too, but no better than most skis, and it's not what you're paying for.
Have fun with them, and keep us posted!