I guess the thing with poss hets is there is no guarantee, if you're dealing with an honest breeder then you should be ok it's all a gamble. That being said I think that's what makes it fun, you roll the dice and you never know what you'll get, well, to a point :) people drop thousands at casinos for the same thing ;)
Chances are what they are, I've seen poss hets throw no visuals one year and a few the next year with the same breeding. Even with 100% you still have that chance of not getting what you want.
If you haven't already purchased I'd say do you research, do diligence and most importantly have fun! Breeding is an exiting and rewarding thing. Good luck!
Fred.