Bit of difference - a lot of men like shit like that - no-one likes muscle implants. 
No difference. It's really the same thing. Breast, muscle, penile, buttock, etc.: implants are pathetic on men or women. The person who does this has such low self esteem I truly feel sorry for him/her. Anyone willing to spend time, money, and risk their life for this has a bigger problem than any implant can correct.
The only exception, in my view, is reconstructive surgery following something like breast cancer.
Muscle implants are fun to look at but only in an amusing and derisive way.
