i use dxextreme alot for flashlights and ion rechargable batteries i will point out for safty that you should only use protected cells and chargers.
i live in the uk and orders take about 2 weeks to arrive.
i have several of the older c3's and 2 of the q5 version both versions are good with long runtimes and appear to be well built.
i would recommend the multimode q5 as it is bright.
i have a nasty habit of dropping flashlights and none of the c3's has failed yet.