As an avid buyer of bits I can reveal tehre are four German sites worth browsing for comparison. They often compete, and sometimes some will have an item for a bit less, then the rest follow. Best example this last year has been the Reverb dropper posts which retail at £299,but can be bought for about £175 delivered from the Fatherland, including the £30 option bleed kit.
Check out Shimano drivetrain and brakes as the comparators... how about a complete SLX groupset (no brakes) for £200... and that's this year's 3x10! Another example is you can buy a pair of SLX brakes for about £112.00, that's a pair, where they sell them for that each at
CRC. Only difference is the levers/hoses are the wrong way round so need swapping when they land. I was about to press the buy it now thing on a pair, then realised that with the reduced shipping costs of a bigger order I can have the M785 XT equivalent brakes for a fiver more. Rude not to.
If you're looking for stuff check the folowing sites. I will also say I have heard no negative feedback from any of them.
Roseversand.com (or .de) (cheaper shipping for orders over 150E)
hibike.de (cheapest Reverb at the moment)
actionsports.de (check out whole groupsets!)
bike-discount.de (amazing deals on Schwalbe tyres, groupsets and brakes)
all of the sites have english versions, some even tell you the prices in sterling.