I bought 3 of these and am happy with them. They work better than any of the previous portable AC's in the past. 
I just checked one after over a week of being on every day and, nothing..... no condensation. Apparently they use the condensation to cool of the air conditioner. Wow, at last they thought of it..... or at least these are the only ones that work in this manner?
Anyway, I'm happy.