To be honest I only bought this because it was so cheap and did not have high expectations for it. I already had the innokin thermo rda (admittedly a little large for the sta) and love it however found it to be too powerful for function, having to redrip every 4 or 5 hits. This changes it completely, take a good couple of dry hits before use but honestly, once it gets started it seems to work flawlessly and I can't wait to try it out on a couple of other rta's. I just wish it was actually slightly larger. Brilliant concept and I hope to see a version 2 of this item! I would definitely recommend!