I've heard the pure dwarfs can be flighty and hard to handle...But chondros aren't a walk in the park either. If you trust both breeders (i.e. you know you'll get what you pay for) then I'd go with the one you want the most and is the least available...i.e. if pure dwarfs are more common, get the chondro, or vice-versa.

I'd personally go for the chondro, but that's just what I like looks-wise.

Good luck whichever you choose. It will be a long time before I can convince myself (and my husband) to put down that much money on a snake.