I always went on the medial part of the calf too. Its the inner diamond area, the part that should "flare" the most. My calves are extremely vascular as well. I just spent a lot of time looking before I stuck the needle in. I had to lay off the tanning for a few weeks while I did it to make it possible with the longer neddles, but IGF is a breeze and that's the only thing I'll be shooting in the calves.