I think you'll find that the vast majority of people here on OCN build their own computers from components pieced together. The reason for this is that the enthusiast then has control over what type of capabilities and quality are built into the machine. The vast majority of pre-built systems use relatively sub-par components in the areas consumers are ordinarily unlikely to understand or care about. The result is generally a less capable, less upgradeable, and less reliable machine in the long run.
I think you should seriously consider taking this opportunity to dive into computer building. If you have the brain power required to run pro-media apps, then you are overqualified to build your own computer.
Just glancing over the specifications of the HP you are looking at, I see some major drawbacks for the price point. A 5400RPM HD? 10GB 1333MHZ RAM? Micro ATX board? Very pathetic looking VRM configuration for a powerful CPU? 460W questionable PSU?
Consider the following:
The HP you are looking at retails for $1200-1400
i7-2600 + 16GB 1600MHZ RAM: http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.746883
Same CPU as is included in the HP. More memory, Faster memory.
GigaByte UD4 MOBO + GigaByte 560Ti GPU: http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.751644
Remarkably better motherboard. Proper heat sinks, big power supply for CPU with heat sinks, full ATX size with plenty of expansion, including the ability to run dual GPU configurations no problem. The GTX560Ti included here is better than the 6850 in the HP by a noteworthy margin. The 560Ti trades blows with an HD69
Lian Li Lancool Case + Windows 7 prof: http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.722407.11-112-154
Very well made case with good air flow. You can add more fans to improve it. Windows Prof instead of Windows Home with the HP here.
Blue-Ray Burner (reads and writes CDs/DVDs also): http://www.newegg.com/Product/Product.aspx?Item=N82E16827136226
The blue ray drive in the HP can only read blue ray. This can read and write, as well as take care of all your other optical needs.
750W Power supply: http://www.newegg.com/Product/Product.aspx?Item=N82E16817703027
This PSU has more than enough overhead and all the connections needed to power a dual GPU system without breaking a sweat, and it is one of the best build power supplies you can buy. 7 year warranty. How many years will HP stand behind that POS PSU they have in their machine?
1TB 7200RPM Hard Drive: http://www.newegg.com/Product/Product.aspx?Item=N82E16822145533
This is the fastest mechanical 7200RPM HD on the market right now. First single platter 1TB drive. You can expect speeds out of this thing 2-3X as good as the one in the HP unit. Much better for media related tasks.
Media Reader: http://www.newegg.com/Product/Product.aspx?Item=N82E16820132022
The HP has a card reader, this will blow that out of the water with more capability and compatibility and convenience.
Apply promo codes: EMCJKJG42, LLSneakOct11, PCP1010.