I have studied at UCL and am now in Leeds. For me there is no contest, Leeds wins hands down. It has a thriving student community and in terms of research, is one of the best universities. Also, I live with two housemates who are doing transport. One is doing the M.A. in Transport economics and the other is doing the M.S.c. in transport planning. They appear to be having a great time and the course is both challenging and rewarding. All the best. Hope to see you in Leeds soon