Upgrade PSU for Studio XPS 435mt

Looking to upgrade the stock PSU of my brother's Dell Studio XPS 435mt. I did quite some research and the best I can come up with is

PC Power & Cooling Silencer PPCS500D 500W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified Active PFC Power Supply
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

He currently only has a Radeon HD 4350 but I'll upgrade his graphics card to something better probably once Radeon R800 series releases. Given other components of the Dell, ideal specs for the new PSU are

- roughly 400W - 450W, I guess 500W is fine, too
- modular would be nice
- 80 PLUS or 80 PLUS Bronze
- 1 x PCI-E 8pin (or, alternatively, 1 x 6+2) is fine, 1x 1EPS+12V 8pin, otherwise no special or large number of cables needed
- *must* be of the "small" ATX size, i.e. 3.39"(H) x 5.91"(W) x 5.51"(D) or, equivalently, 8.6cm (H) x 15cm (W) x 14cm (D)
- I believe an 80mm fan on the rear is better suitable than a 120mm fan on top or bottom of the PSU given the case design. ...I opened the case and believe that there might be an issue with air circulation when going for a PSU with 120mm fan on top (the PSU in the Dell is top mounted and there's basically no space left at all between the PSU and the top of the case). The PSU *must* help get a bit getting hot air out of the Dell--as is well known, the 435mt's cooling sucks

Especially due to the last two bullet points I can't find the "perfect" PSU   Amirite that the Silencer 500 above is about as good as it gets given my desired specs? Or do you know something else?

Thanks for reading