liverpool has tons of pbhell.
A major problem with all this picking and choosing is that you're having to question teaching styles you've never been subjected to. I daresay I hate PBL now, as many others subjected to it will no doubt agree; but still many much smarter people than I swear by it (though equally of more traditional methods).
I remember all those centuries ago (you know, 2004) when I went to the open day at Liverpool. I was told by the prof there that you're expected to direct your application towards their style of teaching; an action which would of course be suicide towards other applications if not of a similar style to Liverpools. He exaggerated the point, and I know people who got in without doing that, but perhaps there's still something in it. I get the impression that they do expect you to base your choices on course structure, and "which other universities have you applied to?" is not an uncommon question. Applying to very different courses may have bad consequences, in addition to suggesting your reasons for applying may be flawed (up for debate, I'll admit).
Oh, about manchester being a polar opposite to camb. As far I can recall it is and it isn't. I think manc is a non-integrated but PBL course, sharing 50% similarity with camb. At 21, though, I'm going somewhat senile. I'll leave this to you younguns applying next year.