Karma's can be a bad idea... if you're either only a novice or intermediate skier they're going to need to be skied too far outside your ability level to make them "work" for you.
Or if you get em too big... I'm 167 pounds and am riding on 177's.... if I had to purchase again I'd get 169's. My previous skis were 181 Atomic GS:11's, and the Karmas even in a 177 are a bit much to manage for me... too much super stiff tail.
Get em in the right size, and make sure you're a proficient enough skier for 'em and I can't think of anything more fun to bomb the mountain on.