It all boils down to efficiency. A really good HP LED can be above 100 lumens/watt. An average HP LED might only be 50. A junk 5mm LED might be 20 or worse.
So, if you're looking at commercial fixtures, don't waste 5 seconds of your time unless the make/model/bin of LED is advertised, or the fixture is being sold by a very well trusted vendor. Sadly, this rules out 99% of LED fixtures out there on the 'net.