is this a bottleneck

Over £500 cheaper ,yours doesn't include mb price.
It'll kill your build stone dead , you can't pair twin fury's with any fx CPU - waste of money - I wouldn't cf a 4gb card either, the only reason you'd need cf is if you're pushing higher res & for that you need 6/8gb vram.
PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i7-4790K 4.0GHz Quad-Core Processor (£245.94 @ Aria PC)
CPU Cooler: RAIJINTEK TRITON 100.5 CFM Sleeve Bearing Liquid CPU Cooler (£59.99 @ Aria PC)
Motherboard: Gigabyte GA-Z97X-Gaming 3 ATX LGA1150 Motherboard (£98.80 @ Aria PC)
Memory: Kingston Savage 16GB (2 x 8GB) DDR3-1866 Memory (£68.30 @ More Computers)
Storage: Samsung 850 EVO-Series 250GB 2.5" Solid State Drive (£55.71 @ Amazon UK)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive (£37.96 @ Amazon UK)
Video Card: Gigabyte Radeon R9 390 8GB Video Card (2-Way CrossFire) (£249.59 @ Aria PC)
Video Card: Gigabyte Radeon R9 390 8GB Video Card (2-Way CrossFire) (£249.59 @ Aria PC)
Case: NZXT H440 (Black/Red) ATX Mid Tower Case (£89.50 @ Aria PC)
Power Supply: Rosewill 1000W 80+ Gold Certified Semi-Modular ATX Power Supply (£115.91 @ Amazon UK)
Total: £1271.29
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-12-31 08:41 GMT+0000

& this is coming from a big fan of amd mate BUT over the £1000 mark I would never ever use an amd cpu , & I'd never use an fx 9*** CPU full stop.