Gaming PC vs. iMac

I'm getting into PC gaming and I need some advice. Should I go with an iMac or a dedicated gaming PC. Here's what I'm looking at. (PS: Price isn't a problem)

Gaming PC:

• 3.2GHz AMD Athlon II X2 processor
• 4GB RAM
• 450W power supply
• 1 TB SATA II hard drive
• Nvidia Geforce GT 520 with 1GB of video memory
• Comes with keyboard, mouse, and windows 7 (no monitor included, I'll get a 25" LED one)
• $579.99

iMac (21.5" version):

• 2.5GHz quad-core Intel Core i5 with 6MB on-chip shared L3 cache
• Built in iSight webcam
• 500GB Hard Drive
• 4GB 1333MHz DDR3 SDRAM
• DVD SuperDrive
• AMD Radeon HD 6750M graphics processor with 512MB of GDDR5 memory
• $1,199.00

I'm thinking of going with the gaming PC because the hard drive is bigger, bigger video memory, and a bigger processor. I am also planning on using it for video editing so I think the gaming PC will be better but, let me know what you think on twitter (@kutarimeikitato or @thebytegaming01)! Also once I get one of these I will do an unboxing of it on my new tech/gaming channel...here http://goo.gl/f2jUY !!!

~Eli