Update:
So, having decided I could do without the additional 2k, I verbally accepted the role.
Had the contract through email today, turns out it's a 37.5 working hours (9-5:30)... I've had several London (city) roles over the years and have only ever seen 9-5 (35 hours), so hadn't even thought to ask this.
So in effect makes this 7% less of an offer once you factor in the additional hours.
I imagine i'm going to look faintly ridiculous if I go back and question this now? In my experience you never work purely your contracted hours anyway (I totally expect to be doing well over the contracted hours, as I do often currently, accountancy if anyone's wondering), but this being within the contract has rubbed me up the wrong way somewhat.
I thought 35 hours was/is the norm for city based accountancy roles...
If you're sure you will be working over those contracted hours anyway, it's no big deal sure. But I do get why expectation vs reality regarding hours would slightly annoy you. I guess in hindsight the focus on the additional 2k detracted you from focusing on smaller details.