The C7T is not the brightest light but it is very well built and the regulation is top notch. Whale of a deal for those of us in the US. Apparently Olight made a few of these OEM for Tenergy a while back and I'm guessing now they are just trying to dump the remainder (Battery Superstore is a storefront for Tenergy). Obviously supply is very limited so please refrain from posting elsewhere.
Yes, the C7T will take a 14500, not sure how much it shortens the overall life of the LED but you should be able to use it without trouble, though I have not done it myself as I don't own any 14500.