Yeah, pretty sure the issues you heard about are related to the 50W. I have two 30s I purchased in February and April. They have been the most reliable, care-free devices I have ever used.
I also have 2 iStick30's, one about 2 months old, the other about 6 wks old... both work perfectly, without a single problem.
Couple things to keep in mind: some of the 50w problems were associated with charging -- and charging does generate heat, which is bad for batteries in general, but apparently especially bad for LiPos -- so it's a good idea to charge early and often, don't let the battery get too drained, because the lower the charge goes, the faster it will charge when you plug it in, and the faster it charges, the more heat is generated. When I plug mine in, there are never more than 2 "flashy squares" worth of charging to be done, so it does get warm, but not hot.
Some warmth in the iStick itself is perfectly normal while charging, but the wallwart itself should not get warm -- if it does, replace it because it really shouldn't get warm; those things are probably the weakest link, in terms of fire hazard; they're cheaply made by the millions, so it's not worth burning down your house over a $1 part. If the iStick itself gets *hot*, either you've let the charge get so low that it has to charge rapidly, generating a lot of heat, or there may be a problem with it. Keeping it charged early and often also will probably extend the battery's life, by avoiding excessive heat.
Also, I always turn mine off while charging. Considering all the problems with the 50w, it seems a small and easy way to make the process just a bit safer.
Andria