Oh no... that is bad news indeed. The 50w iStick is large and has 2 batteries etc. It's not something that interests me, I must say. If the 20w is powerful enough for you, then the 30w is almost identical but has "upgrades" to some of the weak areas of the original one (threads that stripped and the centre pin getting pushed down). There were some reliability issues with the 50w ones, but they might be a thing of the past.
What sort of power are you using? Do you like the small size of the "box mods", or would you consider a "tube mod"?
Look up things like SID (smok) and EVIC v.1. I am NOT saying you should buy one, but that's an alternative.
Otherwise, how about the 30w from Myepack?