Bought brake disc online because of discount but despite using reg number, a range of choices were offered but it wasn't clear what the difference was between options other than brand or price. Turns out the one I ordered was the wrong one. No problem returning it but I could no longer get the online discount as I was now in shop and would have to wait up to 30 minutes for online order to come through. Ended up paying 25% more than I had originally thought for an ordering problem that wasn't of my making. Overall more thought on linking up online and store interface.