I have two HLG 350Rs myself in a 5x5 and I can pull about 2-3 pounds with them. They're great lights, and having two lets you adjust their height differently, and spread them out more than the single board 650R.
That being said, someone I know just got a Scorpion Rspec and that thing is stupid bright compared to my two 350Rs, and the coverage looks great. If you have the spare cash I would buy that instead.