on the ones from staples at least, you have to either bend the flap of the box down (which i couldn't do...i had to ask them to open the box for me)
anything in a pink packing bag is lite-on
anything in a clear bag is Ben Q.
make sure it has a red circle on the front that sayd "8x DL" otherwise you'll end up with the 1625.
staples tends to only stock one of each item in their ocmputer parts section but they keep the rest in the back (easier to monitor theft i assume) if you don't see any out there or they don't have the right one, definitely ask them!
some people have has luck with the $10 coupon that's floating around. there's also a 12% off coupon good for the rest of this week and bring an ink cartridge for another $3 off!