I have three of the 4 foot Aquamedic Ocean Light Plus. (2 x 250W DE + 2 x 54W T5) At the time I purchased them, the only places in Canada that had them were charging triple the US$ prices..so I bought them from CustomAquatics.
I will not give them outstanding marks for build quality, but they have worked well and given me no problems. The design shortcuts make it quite an ordeal to do a bulb change.
Of the three ballasts I received, one of them causes the MH to burn with a much redder spectrum. It is also possible that this is because this ballast is the 2nd on the same circuit. (I've never switched them around to find out because the colour shift has not bothered me...)
I don't think the reflectors do a great job of dispersing the MH light, but it does spread the 2 feet that I need it to.
I went with them because I think my longer term solution is probably LED. This gave me good function at a great price.

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400 gal reef. Established April, 2007. 3 Sequence Dart, RM12-4 skimmer, 2 x OM4Ways, Yellow Tang, Maroon Clown (pair), Blonde Naso Tang, Vlamingi Tang, Foxface Rabbit, Unicorn Tang, 2 Pakistani Butterflies and a few coral gobies
My Tank:
http://www.canreef.com/vbulletin/showthread.php?t=28436