I have no true high opinion of Halfords - in truth I have realistic expectations.
Here's the thing, though - the type of bike shop that recently disappointed me? An LBS - I'd gone, had a little job done because up to then I didn't have the tools, and also to pick up the odd bit and bob. And on the plus side, they sold Velox cloth rim tape for a good price, on the minus side, they made me feel like I was from outer space, asking for a handlebar shim (to step down from oversize clamp, to "normal" MTB bar diameter of 25.4). Shims for stems - not a problem, but shims for handlebars - "That'll have to be some kind of custom job..." - which was said by a spanner of reasonably advanced years (as well as the young-ish, albeit reasonably knowledgeable guy running the place) who've I've known of for decades, as he used to have his own shop, is well known as a local club cyclist, as well as for wheelbuilding.
Now it's only a trivial thing - I'm not trying make out otherwise, or that it's robbed me of any faith in LBSs - and I know I can go online and find a handlebar shim within a few clicks - but all the same - "custom job"? Is that speak just for "We haven't got anything like that in stock..." or "I've never heard of one of them...".
This is an LBS that's a reasonable size, I've bought bikes from them before (son's first bike, a Ridgeback MX 14), is reasonably well stocked, and isn't part of a big chain. Surely they can't be oblivious to the sizes of MTB handlebars available, nor the clamp sizes for stems - if they sold shims for stems clamping on to steerers, is a shim for a handlebar and clamp so alien?
Now I'd go into Halford expecting that sort of talk. But if I can't find that extra bit of insight or not unreasonable knowledge from an LBS, then all I'm left with is greater product choice than somewhere like Halfords - which in fairness, is still a notable plus.