The Dvarw and Kayfun Prime are so called high end atomisers. The original kayfun Prime costs around £100 and the original Dvarw about the same if you can even find it in stock anywhere. Fasttech sell clones of both, most of them seem to be ok but, in my humble opinion, the YFTK clone of the Prime is the best. In terms of flavour and performance the YFTK Prime clone is excellent, probably as good as the authentic at a fraction of the price. Personally I've never tried any atty that beats the Prime, although some come close. I have a doggy and the flavour from it is very good. One major difference between the doggystyle and the Prime is that the Prime has juice flow control. I think jfc is a really good thing but others (such as my misses) disagree. In terms of flavour I think the flavour from the Prime is better than from the doggy, again others might disagree. If you need any advice just ask.