I looked at Be on Money Supermarket and overall the rating was good, but the comments were very mixed, which made me think that customer service is inconsistent. That said, I think all customer service is inconsistent. Where I work, if you get a newbie, chances are they won't fix your problem, or will take an hour to sort it out. I think what's important is how much the customer service varies, and how often. If it's regularly either very good (very polite and helpful, problem quickly resolved) or very bad (some complete numpty, multiple calls, an age to resolve the problem), then that's not good. I can live with service that is either good or very good, with the odd "off day" when I end up with a numpty.
I think all you can do is roll the dice and hope - and switch again if you're not happy
So do I stay with what I know, and the high price tag, or risk it for saving a few hundred a year. Wouldn't be so bad if you could easily switch.