Here are 3 reviews from Newegg about using a low profile video card
Cons: Not a whole lot of room to put normal graphics cards considering the ram slots get in the way. Do your homework, make sure the graphics card you are buying is short (that the card ends where the golden motherboard connector does) and it uses 300w of power. Newegg lets you look at pictures inside the computer for a reason, it's good to know the internal layout of the motherboard before buying any PC.
Cons: Not the best video card, my 6850 wont fit in, so now im stuck with the 4250, because the ram slots are blocking the video card which I think is a big turn down for those who are planning to upgrade a lot, but then again you can just get a smaller video card :\
Cons: Memory slots bracket block normal sized video card.