Pros
The best part was the constant stress of fulfilling time-sheet obligations (~ 95% billable time at a minimum). This gave me sleepless nights and I lost about two stones or nearly 12 kilos in terms of body weight due to stress. This was great as I didn't have to take any gym membership (not that I could afford one). Low starting salary and subsequent pay freezes also meant I could only afford limited food and couldn't eat out or take out. This meant that my caloric intake was limited and I led a healthy fat-free life.
Cons
They take cost-cutting rather seriously. There was a coffee-machine (percolator) in the office when I first started. It was useful as it was the only place I could get decent coffee (as I could barely afford a £2.50 coffee outside on my graduate pay). They threw away the machine citing a monthly expense of £250 on coffee beans (for circa 100 staff). By the time I left, they also kept the tea-bags locked up in a cupboard lest some member of the staff drank more than their usually allocated amount of tea. There was also a time when staff couldn't claim expenses on teas/coffees/bottled water/soft drinks if they are out on client meetings or site visits (not sure if it is still applicable - please check with hiring manager if you're interviewing).