Pros
G-Research has been doing a lot in the last few years to reel in its over zealous security, which has made some things much less painful than they were. They have also made benefits better recently, and now have a competitive pension.
Cons
The security issues are still there - it can take a long time to get anything done and information is often very poorly disseminated. There are also some cultural issues - GR is a medium sized company still learning how to be medium sized, rather than small. There are still a number of people around that could at one point name everyone in the company, and the company still has a 'hero' culture because of it that significantly undervalues team players who don't value selling themself over all else and lets people deemed heros do basically whatever they want with no oversight or questioning (aside from security concerns).