There's a decent new Chinese LED that's 3V, can take a ton of amps, and has more output/lumens than a XHP70.2 or XHP70.3, the SFH55, here: https://budgetlightforum.com/t/-/67698.
I may be the only one in the world that has one and publicly posting about it (from Neal).
Info/pics starting here: https://budgetlightforum.com/t/-/67698/49
Basic #'s: on one 30T at 4.14V: 32.8 amps. Lumens at turn on: 9605
There's nothing new or special as far as amps->lumens goes, but it all can be done by one large LED and at 3V. Same mount size as a SBT90.2 so they can share the same MCPCB, which is also the same pads/mount as a MT-G2.