If UltraLife is the same company I am thinking of they also make an RO/DI unit. I purchased this unit about 6 months ago and have had no problems with it. I have not used any of their equipment other than that, I would fork out the extra $50 or so for the IceCap ballast (660). I think I paid $175 or $199 for just the ballast, then the end-caps and bulbs were over and above that.
The Icecap 430 ballast can run 330 watts as well using 3x48" lamps. And usually sells for around $160
And the Icecap 660 ballast can run 440 watts of VHO using 4x48" lamps. And it usually sells for around $180
Thats an extra bulb over the one in the auction, and the 660 Ballast is only $50 more. I use an Icecap 660, and it's worked flawless with 4x48" bulbs for over 6 months now. And temperature of the ballast has NEVER been a problem, as it's only ever slightly warm to the touch.