^ this is true.
look at the Are 51. using xpg chips, when xm-l2 are out. if you built it right, you can even get better thermal performance = better light output.
also with DIY, you retain the heatsink / fans / drivers.... in a normal panel, they want you to keep buying the "whole package" so they make money on every part you buy ( case , fans, drivers, heatsink, chips, lens.... ). that can't be said for a company like HGL though, as there suppose to just switch out LED clusters when they make new ones.. who knows though as it's never happened yet to see the process, and how much they charge for the clusters..
but also then to buy a panel is far cheaper, and easier then DIY...