Pros
You are left to your own devices at lot, even as a PL. Tech choice and similar is entirely up to you, so if you joined from somewhere else and already kind of know how to do things it's ideal. Working hours are sensible, free lunch is good, salary is good and pension is very good. The employee trust benefits would likely end up being generous later. Most of your colleagues are decent, and internal processes very light generally. Projects are wide ranging and interesting, and you have quite a lot of free choice in what you work on, your line manager certainly doesn't choose for you.
Cons
Management seen distracted with constant spinouts, marketing, and acting as the furniture police. Any internal comms is often late, confusing, and clearly written by a committee. Lab equipment is poor and often broken or missing, if you can buy something on the clients money it's fine but you shouldn't have to be buying the client allen keys every time. Getting approval for any internal purchase is like pulling teeth and so we end up with half the lab equipment being older than me. When I joined your first task was having to beg for a 2nd monitor, it's improved only slightly since then. No one ever seems to have got fired for poor performance, so there is a fair amount of dead weight hanging around, resulting in terrible utilisation which makes us uncompetitive. If you find an ineffective coworker your only option is to just avoid asking them anything in the future and hope they leave out of boredom, therefore you get super paranoid when interviewing as the decision seems irreversible. The appraisal system should catch this, but as you can choose who your appraiser gets feedback from, they can just avoid asking you if they suspect anything other than the most glowing remarks. There is no ability to appraise "up" either, if you don't like your line manager you should just move. Don't expect any formal feedback at anything other than yearly intervals, if that.