Buy them from a well established seed bank, you shoudl'nt have any problems.
a friend of mine wont buy femi seeds cos he says there unstable, rekons hes had alot of them go hermie on him, that might be a load of shit though..
personally i'd rather get a standard pack of beans grow a few and go with the gamble of getting a few males, its a pain in the ass, but once you have some females you can keep a mother and take clones from her, worth doing in the long run.


peace.