I am another loyal 808 user, me and the wife both started with V2, but they are very limited on what they offer, so started researching more and found V4L, which had a lot more flavors and all do bigger batteries like the DAV and Zeus, and as my wife is happy sticking with cig like batteries, and we already had over 30 808 clearo's, I wanted to stay with 808 device, memorial weekend I bought my 1st DAV, and have loved it so much, just ordered a 2nd one today, already spent a lot on 808 devices, not going start all over with 501 and have to deal with different threading devices for me and the wife, yes I admit it is harder to find things with 808, but am happy with what I have right now, and even though some say V4L is expensive, I think the quality of there products makes the price worthwhile.