Quote Originally Posted by RackitMan
Too much expense for a small hobbyist. If I ever take my designs or grows to the next level, I would certainly invest.
A $200 meter is too expensive compared to what, exactly? Especially one that will accurately measure light output and give you a number that matters for LEDs.

Also you should obtain a kill-a-watt meter for about $40. This will tell you exactly how much power each panel is drawing (that commercial 120w is likely only pulling 60-90w) and that will give you a better idea of what's going to perform better. I would wager the reason you're wagering on your panel matching or winning is because that 120w isn't really pulling what it claims and thus your unit is likely hurting your eyes just as much as the commercial one.