HLG is for sure a good selection, but I wouldn't doubt Atreum would most likely match their price if you just were to ask.
Keep in mind, the HLG 144's are a much smaller board size(2.77"X3.75"), the same size as they use for their Elite96 boards, than the Atreums and have more of a concentration of leds in one place. Atreum uses the same sized board as their 288(10.25"X10.25"), just half of the diodes.
HLG 144's require heat sinking, but I can guarantee you the Atreums DONT.
And from what I can read and find out, that couple of bucks you save is just going to 4 heatsinks, costing you significantly more in the end. They include thermal adhesive pads for a reason.
Atreums will give you a much better spread of your diodes across your canopy compared to basically 4 point sources of light with the HLGs.
So for that reason, if you're set on using HLG, I'd recommend the 120's or 132's.
High Efficiency LED Light Engines. 132pcs Lumileds 2835HE
horticulturelightinggroup.com