Mounted a YD5050 5000K in a newly bought SupFire GT60 - 3 cell, 52 mm head zoomie, de-lens of course. Decided to keep stock driver because of the 2 switches and additional tail LED's from a separate switch, bought here on Ali, but US warehouse - got it in a blinding 2 days!
Throw went from 30 kcd to 240 kcd, lumens down from 1300 to 850 or so. Only measured 4 amps on max, even after jumpering out the resistors feeding the LED-. It boosted amps only slightly. It's a "battery pack" light with 3 ~2700 mAh 18650's wrapped as one in parallel (3P), directly wired with no springs. You can remove it by desoldering the batt wires from the driver.
This was my plan for this light mod, though wasn't sure if 3P or 3S/buck cell configuration and was hoping I could get more amps. Stock it did about 6 amps with the stock LED so I was hoping for 6 amps with the YD5050 but it's high Vf must have reduced it. The wires are already 18 AWG - I swapped with Turnigy 18 AWG but probably made no difference in amps.
It would probably do over 300 kcd with more amps. It's basically SupFire quality. They used to be a popular light for us because of the quality, price and mod-ability.