I think the work placement is Bath's big selling point and I'm sure was a big plus when applying for jobs.
I agree it is one of their selling points but I disagree that it helps with employment in the long-term. I know quite a few Baths math graduates, and their placements were rather low quality: some had to find their own placements with local firms, working on rather low level stuff unrelated to maths. Many Bath graduates do indeed obtain jobs with their placement companies, but they could arguably have done better in the job market, given their A level/degree results. So e.g. they get actuarial training contracts with local smallish firms, rather than with big national firms, but doing the latter would probably help more in the long run.
Her bf hated his course (mostly down to him not having picked the right course to be fair) but his biggest issue was applying for graduate jobs afterwards as "maths & physics" never seemed to be an option on the drop down lists on online applications, which meant he was automatically rejected. All sorted now though, though there were a few difficult interview questions about why both, and not one or the other.
I'm pretty sure that this is not representative - either being automatically rejected on a technicality, or it being viewed as a negative point that he studied maths with physics. In general mathematical physicists are in extremely high demand in the UK.
I wouldn't put Surrey just because their official offer is AAB: in practice much better maths/physics departments/universities do accept AAB even when their official offer is AAA/A*AA. I would advise going to some open days and chatting to admissions tutors about this. A student with Oxbridge potential would probably find the Surrey courses at too low a level.
Bear in mind that many theoretical physicists are based in maths departments in the UK and accordingly many maths degrees contain a large content of physics. Mathematical physics or maths with physics are not combination degrees: maths and physics are a continuum, with modern mathematics overlapping with physics and modern physics creating new mathematics.