Grolux? Any good?

My previous HPS recently died out on me, so I have been keeping my two plants which are currently flowering under my 400 watt MH bulb. I assume the plants will be fine, but I realize the need for the red spectrum via the HPS bulb. Upon looking for a new bulb online, I had come across the Hortilux 400 watt, and another Model called "Grolux", by Sylvania. Growlux claims to deliver 58,000 lumens, as apposed to the Hortilux which outputs 55,000 lumens. Also, the Growlux is 69.95, while the Hortilux is almost $100 USD.

Does any one have any experience with any of these lights? Should I trust the Growlux over the Hortilux?

http://www.bghydro.com/BGH/itemdesc.asp?ic=HLRBHPS04GL&eq=&Tp=

I just buy the cheap $20 ones from Lowes.