HUGE proponent of June - I took it then, albeit on top of summer school and work, but it was really nice because the June test is in afternoon, not morning!
I ended up retaking in October, but I feel like that was a better idea.
One of my friends took it in October for the first time and BOMBED (as in sub-140) and then realized he wouldn't be able to retake until February (the December test is horrible because of finals) so he is now postponing law school a year.