It depends.
- Scenario one: You have to stay in California, for example your wife or your husband has a well established job in SD: You are doomed to choose the research track just below the regular track even if it is two years more.
- Scenario two: You are 100% sure that you want to do academics AND making 60K a year instead of attending income is no big deal to you: Then doing research track at UCSD is reasonable. Even if you don't publish lots of papers, it gives you a lot of advantage to find an academic job esp if the job opening is at UCSD itself. Finding an academic job, not only for radiology, but also for most fields is hard in California. In the current job market, Big California programs hire either internal candidates or someone with 4 pages of publications from MGH.
- Scenario three: You want to do private practice or your are not sure: Then doing one extra year of research track is A WASTE of time. Don't do it unless you are dying to stay in SD. If you want to torture yourself by doing an extra year of training, at least spend it doing a second fellowship or a two year neuro fellowship or even something like quality fellowship or informatics fellowship, all of which are more useful than the research year at the beginning of your fellowship.
Having said that, if you are single and you don't mind having a light relaxed schedule for a year especially after medical school and internship and you don't need a lot of money, San Diego is a fun place to be for a year with a relatively relaxed schedule. You won't find such a special time in the future. Still the research year will be A WASTE of time, but don't forget that occasionally the best times in your life have been the ones that you thought you had wasted.
Good Luck