is an istick worth it?
Absolutely worth it to me. I have one and will get another next month. I only used ego threaded toppers so use the adapter that comes with the istick. The threads on mine are smooth as silk so even if I used the 510 threaded devices I wouldn't think there would be a problem as long as they are taken care of. ie: do not cross thread, do not over tighten and keep the threads clean.