Reviews: $850 AMD Gaming Build

I'm looking to build a new rig (my first time) and need it specifically for gaming (BF4 in 1080p) and S/W development purposes. The CPU I've selected will take care of my Multitasking and Multicore needs. And Oh! I'll probably OC in the future but its not my immediate concern.

My budget is specifically INR 55000 (~850 USD). I live in New Delhi, India so NewEgg and PCPartsPicker recommendations are pretty much useless. Try searching for the same products here, as these give a fair idea of availability here:
http://www.flipkart.com/
http://www.snapdeal.com/
http://www.ebay.in/
http://www.amazon.in/

I need opinion for the my specs. regarding the following:
1. Any possible bottlenecks
2. Any possible power need shortages (PSU)
3. Any price-performance alternative. (Except where I've put a FINAL tag).
4. Any general advice.

My specs are:

CPU: (FINAL) AMD FX 6300 (FD6300WMHKBOX)

Mobo: (FINAL) ASUS M5A97 R2.0 (ROG) {After much research I've settled for this. Heck even ASUS recommends me this for light OC. So not spending on EVO (not going for Crossfire) or 990X or 990FX models}

RAM: In a fix here. Require only 8GB 1600 DDR3. The ASUS mobo QVL was absolute horse-shit, so there. Was thinking maybe one of these: (Dual channel is what I really want, but wondering if it'll make some serious difference? )
1. Kingston HyperX DDR3 (KHX1600C9D3B1K2/8GX) (This one's a Dual-channel, I'm hoping against hell. The XMP doesn't worry me, ASUS's got DOCP)
2. Kingston HyperX DDR3 (KHX1600C10D3B1/8G) {No kit here. Can't seem to get the difference between an 8GX and an 8G}
3. Corsair Vengeance DDR3 (CMZ8GX3M1A1600C10) {8GB single. Worried it might be too large and clash with any after-market coolers in the future.}
4. G.Skill RipjawsX DDR3 (F3-12800CL9D-8GBXL) {The dream. Dual Channel. But its straining my budget. Or maybe I should go for single channel (F3-12800CL9S-4GBXL). }

GPU: Again torn here. I really want to get a R9 270X 2GB. Just wondering which brand {No HAWK or TOXIC (they are too high for my budget)}:
1. MSI (Twin Frozr) {Benchmarks tell me I should get this one.}
2. ASUS Direct CU II or the ASUS Direct CU II Top (this one's a bit expensive) {These are so long I'm worried they'll crap up my case (given later)}
3. Sapphire VAPOR-X (for some reason cheaper than the MSI one. Beware this model's got a GPU clock of 1050 MHz only. This is NOT the OC one)
4. XFX (killing my budget. Most expensive among mentioned here. This model is NOT the OC Black Edition. Clock is only 1000 MHz)

PSU: NEED HELP. Want to get a 550W-600W, just to be on the safe side. Was wondering about the Corsair CX series (CMPSU-600CXV2UK/CMPS- CX600W). Or maybe Seasonic. I'm out of my depth here.

HDD: Will try and get a WD 7200 RPM drive. Or maybe a Seagate barracuda? You tell me.

CASE: Some serious trouble. The uncertainty with the GPU is causing great problems here. I really don't want to spend much on this. Just need good dimensions (long GPU and aftermarket coolers like CM Hyper-212 EVO and proper airflow. Will probably go with one of these:
1. Antec X1/X1-E Mid-Tower ATX
2. Antec V1 Mid-Tower ATX.
{Getting good cases in India is a real pain in the arse. No one seems to keep cheap-sturdy-spacious-airy cases}

Thanks for bearing with the length of this post. And thanks in advance for the answers.