First of all, it is in the different places. MRU is in Vilnius the capital of Lithuania. Vilnius is small and cosy city. But if you want to live in a most international city you should choose London where is RHU.
Secondly, RHU students take four courses in each term of the first year and then courses in the second year build on the knowledge gained in the first year. In the final year, students carry out independent research projects in small groups. Whereas, MRU students get schedule of courses each year. Also, they should write course paper in the second and the third courses and final paper in the last course.
Moreover, study programmes of psychology are a little bit different in every university. For example, MRU acquire not only psychologists but also wide celibre specialists because they also study introduction to philosophy, the culture of lithuanian language and logic. Furthermore, students have some disciplines of speciality in the first year. It is methods of psychological researches, the history of psychology, communication skills and positive thinkinhg. Meanwhile, RHU disciplines is based on speciality courses from the first semester. It is introductory courses in lifespan development, biological psychology, learning and memory, abnormal psychology, and self and society. But also i want to notice that many points are similar in both universities. MRU and RHU students have sensation and perception course in the first year.
Finally, study term is not the same. If you want to study bachelor three year you should learn in Royal Holloway University, but if you want to be a student one year longer you might choose Mykolas Romeris University.
To sum up, i believe that RHU is really good choice because there are people from different world places, work excellent specialists and students do many researches during they study. However, i live in Lithuania and here is my friends, family and native location so i entered MRU.Read more about study programmes here:
http://www.mruni.eu/en/padaliniai/fakultetai/politikos_fakultetas/katedros/psichologijos_katedra/studijos/
http://www.pc.rhul.ac.uk/web/Studying/studying.asp
