what you have to remember is this is with all T5 bulbs punching PAR of 600+ on the sandbed showing this shimmer.....pull the T5 down a few notches and the shimmer is better. Still if you want the best shimmer go MH all the way
Its quite a nice light, the LEDs get rid of the flat look that T5 have and the T5 give the bright look that LED dont have
I will be taking some spectrum readings in the next few days or after easter so keep a look out