i've had my own issues with
halfords, have got so p1issed and complained online on their website as well! no point really.. didn't it appear on tv as well on some programme? about halfords bad customer service? cant remember.
i find evans to be very friendly and knowledgeable in comparison. issue with evans is i've never gone in tehir and come out without spending on something i didnt really want!!
having said that the reality is - gone are the days that you can depend on a shop-floor service for sound advise and decision making. they're all doing a 'shift', with half of their mind possibly on making numbers other half possibly on their studies or whatever else they do with their time outside.
so own research, fact findings, forums like this are key to making your own sound decisions.
shop floors are still needed, often for the final touch and feel before the purchase decision.