Bought my last 2 bikes (frame only) online and never had any problems. But like Smokin Joe I know exactly the dimensions I need for a good fit, and this is where an LBS can be handy. Nothing beats trying a bike out for size and buying online could be a risk unless you know exactly what you need. That said, the only bike I've ever bought that didn't fit perfectly came from the LBS (coming from MTB to my first road bike I realised after 6 months it was a bit too small).
Never had any problems with warranty returns either thankfully. My current good frame, bought from
Chain Reaction had to go back and it was all sorted and back to me within a week. Compare that to the 4 weeks it took to get a chainset sorted through my LBS. Buying local brings no guarantees of quick efficient service as warranty returns are as much to do with the manufacturer as the retailer.
I can recommend
Chain Reaction,
Probikekit, and
Cycling Bargains. Unfortunately, apart from
Chain Reaction they seem to have very little in the way of complete bikes, but they are always my first port of call as the customer service from all 3 has been fantastic. I hear few bad things said about
Wiggle as well.
If you're prepared to post stuff back if it goes wrong, are confident in setting it up yourself, know exactly the size you need and buy from reputable dealers buying online can be worth it.
