Regarding the Par meter, I dunno if Par readings from LED really reflect with Par readings from T5 or MH. Different wavelengths are what I was told. Even the Par meter itself has two different modes, one to read sunlight, the other for artificial. I don't if either of those readings were intended for LEDs.
Why I say this is that I have used a Par meter for my LED panel I bought off of eBay. At the level I placed my SPS, the Par reading was only ~150. If that was T5 or MH reading, there was no way it would be sufficient for life; however, they not only survived but grew.
So if you do use a Par meter, be cautious of Par numbers from tests done on T5 and MH that it might not reflect to how effective your LED panel is working.