I have the dial-a-volt from v4l and the vamo v2, and I only use carto
tanks. But I think a smileomizer is just a cartomizer with a rubbery tip, I've heard they are quite nice but never got my hands on one though because of $ probs. Between the two I would definitely choose the vamo v2. Watch dropping the vamo though because I dropped it like twice and the top cap became all slidy and popped off all the time, but I fixed that by packing tin foil in the cap and now it works like it's new. I love both of them.