What more can one say about these units that hasn't been said? The score speaks for itself, really. This thing has the best ripple control I've seen, it's efficient, and it's cheap compared to what little competition it actually does have. I seriously cannot think of one thing to complain about on this little guy. Yeah, having three total PCI-E connectors is a little odd, but that's no complaint for a unit this small. If you need to power two video cards, you're usually in need of something a little bigger than 550 watts.
The Good:😀
excellent voltage stability
beyond excellent ripple control
fully modular
affordable
lots of included goodies
Easily. I run a similar system (not this one) on an XFX XTR 550W PSU.
We need to know exactly what PSU you have. Wattage alone is not enough of a guide, nor is efficiency (Bronze, Gold...) We need to know how durable it is and how high-performance the parts are and we can only tell if we know who makes it.
EDIT
My only excuse was that the G2 had not yet been released, and I got a $20 rebate on the XTR