I've ordered from them three or four times a year for the past two or three years. Never a problem. They've become my default IBS (Internet Bike Shop).
Their currency conversion estimates are a bit more than my bank charges. It's nice that they err on the side of caution.
Bear in mind that their shipping to the US is flat-rate (about $23) via Royal Mail Global Priority, which converts to Express Mail Overnight when it hits JFK. There is no choice of carriers. I delay ordering until I have a few hundred dollars worth, then order a bunch of stuff at once. It spreads out the shipping fee.
As for delivery, I order over the weekend, it ships Monday or Tuesday, hits JFK on Wednesday or Thursday and my doorstep around 1pm on Thursday or Friday. You'll need to sign for it or pick it up at the post office on the following day. So choose your shipping address carefully.