You MUST match the wattage of the bulb and ballast. You can't run a 250w bulb in a 175w ballast for example. You would be fine with a 175w ballast and a 175w Iwaski 15k bulb. You will get as much PAR from that bulb as many 250's and it's a bright white color.
Originally Posted by jrp1588
wow, that's quite a markup. I wonder what the difference is? I imagine the reflector quality isn't as good, but reflectors aren't THAT expensive
You get what you pay for. A good, quality reflector will run around $100 or more.