Hey, I'm currently on the MSc Security Studies programme at UCL. On the whole I am pleased with the programme, the department facilities (which have recently been completely refurbished and we've extended into the adjacent town house on Tavistock Square giving us more space), and the quality of teaching. The School of Public Policy enjoys promoting itself as the only graduate focused political science department in the country (which will continue until 2015 when it is introducing PPE and Politics as its first undergraduate degrees). The seminar series organised by the department attracts high profile dignitaries, this year's speakers included the former Foreign Secretary Jack Straw (whom is also an honorary Professor of the department), Jonathan Powell spoke on the issues of terrorism (Blair's ex-Chief of Staff 1997-2007), and we even had Nicola Sturgeon the Deputy First Minister talk about Scottish independence on the same day that Osborne formally declared that the UK would not allow the Scottish to keep pound sterling.
The course attracts (and this goes for the department as well) a broad mix of students from a range of backgrounds although most have studied political science. There seems to be a fair few Oxford graduates (but interestingly few Cambridge grads) spread across the Master's programmes including Security Studies. My main reason for choosing the Security Studies course at UCL over others of it's kind was because of UCL's global footprint (4th in the world according to the QS, and highly ranked/ top 5 for politics in every national league table), and the highly employable skills afforded to students due to the compulsory Quantitative Research Methods and Qualitative Research Methods modules (which you choose between introduction and advanced). Most likely, unless of course you have a knowledge of statistics, and Stata the data analysis software you will be expected to use, you will find Quantitative Research Methods challenging, but also very rewarding. I have to be honest, I did not enjoy the module all the time, it was very difficult (I thought that I might fail it). However, somehow I managed to get a Distinction, and afterwards felt hugely proud to have accomplished this in such a skills based module.
The programme itself is quite theoretical. It seems that most of the department's lecturers prefer quantitative research methods for dissertations (I say this as I am just getting into this phase of the course). You can pick optional modules from outside of the department that can be more arts based, i.e I chose to do the Russian politics module which is taught by SSEES and the coursework + exam follows your typical arts based format.
In terms of the programme's reputation, well I can't specifically say (I'm probably biased) but it seems to have attracted some intelligent students. Moreover, the course will put you in good stead for jobs in NGO/IGO and think tanks as most expect applicants to have formal quantitative and qualitative research skills.
The department and UCL as a whole are very good at using there reputation to attract employers and help students go on to PhD study or further education. I'm off to St Andrews next September for example.