Im looking of advice on a custom build pc Please help

Hey Im looking to buy a new Custom built pc i was wondering if this is decent im a casual gamer im just asking is this ohk for that and will the parts mix well err here are the specs and is the site trusable ?  CSPECILIST.com


Case
COOLERMASTER ELITE 310 BLUE CASE

Processor (CPU)
Intel® Core™i5-2500k Quad Core (3.30GHz, 6MB Cache) + HD Graphics

Motherboard
ASUS® P8Z68-V/GEN3: PCI-E 3.0 READY, SLI, CROSSFIREX***SPECIAL***

Memory (RAM)
8GB SAMSUNG DUAL-DDR3 1333MHz (2 X 4GB)

Graphics Card
1GB AMD RADEON™ HD6850 - 2 DVI,HDMI, DP - DX® 11, Eyefinity 3 Capable

Memory - 1st Hard Disk
500GB SATA-II 3-Gb/s HARD DRIVE WITH 16MB CACHE (7,200rpm)

2nd Hard Disk
250GB SATA-II 3-Gb/s HARD DRIVE WITH 8MB CACHE (7,200rpm)

1st DVD/BLU-RAY Drive
24x DUAL LAYER DVD WRITER ±R/±RW/RAM

Memory Card Reader
INTERNAL 52 IN 1 CARD READER (XD, MS, CF, SD, etc) + 1 x USB 2.0 PORT

Power Supply
600W Quiet 80 PLUS Quad Rail PSU + 120mm Case Fan (£59)

Processor Cooling
SUPER QUIET 22dBA TRIPLE COPPER HEATPIPE INTEL CPU COOLER (£19)

Sound Card
ONBOARD 6 CHANNEL (5.1) HIGH DEF AUDIO (AS STANDARD)

Network Facilities
GIGABIT LAN & DUAL-BAND WIRELESS 802.11N 450Mbps PCI-E CARD (£36)

USB Options
6 x USB 2.0 PORTS @ BACK PANEL (MIN 2 FRONT PORTS) AS STANDARD

Operating System
Genuine Windows 7 Home Premium 64 Bit - inc DVD & Licence (£79)

Office Software
FREE Microsoft® Office Starter 2010 (Limited functionality Word & Excel)

Anti-Virus
NORTON ANTI-VIRUS 2012 - 1 Year Licence for 1 PC (£14)

Monitor
22" Widescreen TFT 1920 x1080 2MS D-Sub, DVI, 21.6" Panel (£99)

DVI-D & HDMI Monitor Cables
2 x 2 METRE DVI-D CABLE (£9)

Keyboard & Mouse
LOGITECH® K200 USB MEDIA KEYBOARD (£10)

Mouse
LOGITECH® OPTICAL USB MOUSE (£5)

Warranty
3 Year Standard Warranty (1 Month Collect & Return, 1 Year Parts, 3 Year Labour)

Delivery
PCS EXTRA-CARE DIAMOND DELIVERY - MON-FRI, PRE-NOON (£9)

Build Time
Standard Build - Approximately 10 to 12 working days