If I had it to do over again, I would just go with a VV mod and save the $$ and space. I now have 3.7v, 5v, 6v & reg. 510's, 808's etc. It would be so much easier if I just had a darn VV and didn't have to worry about which mod goes with which atty/carto/etc.
A VV or a VV feeder is on my...