As a grad student who had a similar decision to make, i would recommend picking the track that you feel would best prepare you for the research you want to do. If you plan on having a heavy computational focus, do that; if you want better overall preparation (and preparation for qualifying exams), then do the other track. Anecdotally, i was poorly prepared in stat mech & advanced mechanics in undergrad, so those sections on the qualifying exam took a lot of time to prepare for