MSc Computer Science (conversion) - how do UK unis compare?

Hey all,
I am looking to apply for a MSc Computer Science conversion masters for next year and would like to know how the unis that offer those programmes (UCL/Bristol/Newcastle/Nottingham/Birmingham/etc.) compare, mostly in terms of employability (I would like to land a role in London afterwards).
I graduated with a BA in Politics & Econ (mostly Politics) from UCL; however, I went through a lot mentally and my grades from 2nd and 3rd year are very average and so I don't think I'll get into the UCL programme. Also, even though it's geared towards non-CS graduates from any discipline, some linkedin stalking reveals most UCL candidates have a maths-heavy degree (e.g. engineering, accounting, etc.), which I also don't have.
So, in case I don't get into UCL, I would love to hear from people who completed this programme in other universities (or know someone who did).
Thanks in advance!