I'm thinking it's worth spending a bit extra.
I have 2 AW IMR 18650s that last me almost 2 days each. I also have a couple of old high-drain 18650s I was given and it would probably be worth testing them. One was at 4 v and the other 3.9 so on their last legs anyway.
I've just ordered an Xtar charger because I don't trust the trustfire. It works for a single battery right now, but if I have two in the LEDs blink for ages then settle down so one has a red LED, the other pulsing red/orsange. It just can't charge two at the same time.