New grower

HLG 300 quantum boards - that is what I am going to upgrade to

 

2

 

I like the idea of 8x QB132 boards and 2x HLG-320H-2100 drivers. you could also do it with 2x LRS-350-36 driver if you want to save somer money.
Perfect fit and coverage for a 4X4 tent for both veg and flower seed to harvest and low enough heat from the boards even at full power that no heatsinks are required.
step up would be 2x QB288V2 with slate 2 heatsink combo's and an HLG-600H-54 to run all 4 boards or divide it with 2x HLG-320H-54 or HLG-240H-54. The HLG-240H-54 would run the boards ar less than maximum power so they would run cooler and more efficient (still PLENTLY of light)

The HLG-300 mentions is basically a prebuilt kit ready to hang consisting of a single pair of the QB288 boards - good for a 4x4 to veg but recommended flowering is only 3x3'. unless you supplement this light with something else it's a bit low to flower in a 4x4 space based on their recommendations.
edit: saw now that the HLG-300 recommendation was made to 2 units for that size tent.

 

depends on your situation
the quantum boards willl def. be better but cost alot more
you can add to what you already have but may still NOT get the output you desire
I cant afford the quantums right now so I using cheap ones - just not getting monster output with what I have

 

I would need to see the wattage that is what makes the diff. more watts more output with QB's especially

 

Maybe you can try the new series. They are better.

 

Probably this new series
MarsII 900 veg spectrum LED grow light custom spectrum

 

I have seen the results and so far the best is from HLG quantums
I plan on getting several of the QB304 putting two of them on the dual heatsinks as soon as I can afford to

 

I built this today. Was about $500-ish.

 

Mars II and Mars pro II