So far straight shea butter has been my favorite, but I'm still fairly new at it. Gotta let it get warm enough to spread.
@turnrow, I use a thick water-based gel called Babe Lube from Babeland. Works great on the Aneros too. I use just enough for a seal. If you use too much, it might get sucked into the pump.
Cant wait to try this when using my helix. Try Wim Hof breathing too!