I've got a Cree MCE 3-2 torch (similar to the SSC P7 torch) from Deal Extreme.

Quite often, after not being turned on for a day or more, it will turn on at the usual brightness and after 2 – 3 seconds will drop to very low power (as it does when the cells are near empty). If I then take out the cell and put it back in again the torch seems fine, holding the usual level of brightness with no problem.

I am using the Trustfire un protected 2500mAh 18650 cells. Does this sound like cheap/crap/damaged cells rather than a problem with the torch. I've already had the tail switch apart and no swarf of other bits fell out

Any help appreciated

One of mine did that but was fixed by messing with the switch, so that's of no use to you. Try this thread for more info:
http://www.candlepowerforums.com/vb/showthread.php?t=227518

Trustfire un protected

ie can be trusted to catch fire at inopportune moments ?

Thanks zippy Ill have a look at that thread.

Simon, they've not done so yet,but I always keep an eye on em while charging 😉

Have a look at this little thread I put up – P7 fault/fix
Very basic torches as it turns out. You may have a battery issue but if not check the switch (easy to remove, replace) and especially the connector with the little screw as that was the issue with mine.