Pros
Very worthy work, on machines for treating cancer. It's hard to think of many more worthwhile causes. Consequenty, most fellow staff are quite progressive and keen on inclusivity which I view as a good thing. There are excellent employee resource groups for sports and social clubs, to professional support for new starters etc. Office space is quite pleasant, if you like large open-plan offices. Excellent food at very reasonable prices in the canteen.
Cons
Weak salary growth. So don't believe any suggestion there's more to come when you negotiate your starting salary! Gradually decreasing flexibility for staff. Was 2 days expected in office, 2 years ago, then 3 until recently, and soon will be 4. It appears the new CEO is following the trend of tech-bro executives who love to see people pointlessly commuting into buildings to have teams calls, giving a nice warm feeling for the execs as they wander the open offics seeing plenty of drones filling all the desks and looking busy, while spoiling the opportunity for focussed work in home offices that a proper flexible working policy would enable. Won't be surprised if the full return to office follows. For managers, it already has gone to 5 days/week in office. 10% of staff (they claim mostly in middle-management layers) will soon be cut. It remains to be seen whether those that remain will be expected to pick up more workload.