No there are no negatives - a female plant is a female plant regardless of how it was created. Unless you plan to breed more feminized plants, you will still need to find a male though.
Thank you Natural.
Things I keep hearing are the possiility of hermies, but that exists with regs aswell. But the otherone that has kept me worried is when someone said that there could be problems after few generations when bred from femmed. He didnt really explain it well though... so maybe just another myth?