This company tries to take as much as possible from you by giving back as little as possible. In nearly 3 years of working for them, the only pay increase I was able to get out of them was £5k/year - I've felt fully exploited, to say the least.
The workload often implies overtime, and the responsibilities keep growing if you get better at your job but in no way do they reward you for the growing efforts with either a promotion or a raise.
These people are the opposite of transparent and will mess you around for ages if you wish for any career progression.
This agency is not employee focused, all they care about is their margins at the end of the year - If people quit, fine, doesn't matter, they'll just get some cheaper labour from either Argentina, India or UK graduates