keep it to the front so you don't fuck your shoulders up..........if you must go to the back keep it light with perfect form and try thumbless grip.it makes you go lighter and pull with your elbows leading instead of pulling and feeling it in your bi's............
Yeah bro I would say that you could incorporate any type of variation except behind the neck which are too dangerous and activate too much of your rear delts and put your rotator cuffs in a very dangerous position etc. Front, v-bar, close-grip, reverse-grip, but not behind the neck. Good luck!!