LED Supplemental Lighting

Most of the threads here dedicated to LED lighting seem to be about LEDs exclusively. However, I've heard that LED lights work better as supplemental lights than as main lights. My grow room right now is in my attic, but the electrical wiring that runs up there is only a 15-amp line. This line powers the entire upstairs, including my brother's air conditioner, three computers, and an occasional hair dryer. So far, the breaker has only tripped once, but I'm still apprehensive about putting in more HID lighting than my current 400 watt setup.

So anyway, I was thinking it would be interesting to try supplementing my HPS light with some LEDs. That way, I could get the best of both worlds, I hope. So... does anyone have experience using supplemental LEDs? Would it be better to use blue or mixed spectrum lights with a HPS light? I'm leaning towards getting these:

High Tech Garden Supply

Still, I'm open to suggestion. If I did get them, I'd be happy to do a grow log for anyone interested, but probably not until next spring, since my attic is inhospitable in the winter.

I'm doing this myself since...well today ;) kinda curious to see what kind of results I'll get! I've gone from all CFL (in prior grows) to vegging with CFL & LED (cheap 225 LED blue panel) but now that my flowering HPS was delivered...I couldn't resist swapping the CFL's (1 X 125 watt + 1 X 45 watts) with the HPS (150 watter) and supplement that with the blue LED panel ...so far so good, knock on wood!