I've stayed in both and there's pro and cons to each.
San An has a great atmosphere, there's always something going on at all hours of the night and ultimately the likes of Mambo and Cafe Del Mar are there on the sunset strip. Savannah's is also there which is personal favourite. Also worth checking out is the Orange Corner. Great little bar to eat in during the day and always a nice vibe in there I've found.
The flip side being I do feel it's a bit of a younger feel with the likes of the West End which attracts a slightly different crowd and really aint my thing and although there is the likes of Eden, Es Paradise and Ibiza Rocks all within easy reach. It is cheaper (of so I've found) compared with the likes of PDB which is another advantage.
PDB - Stayed there for the last 2 years and loved it. There's a lot going on during the day with the likes of Space, Bora Bora and Ushuaia but it tends to quite about 2 or 3am until Space closes which I kinda prefer. If you're the kinda folks who like a bit of down time to relax and maybe get a few hours sleep one night it is ideal for that.
I've found a lot more Italian and German crowds frequent PDB but I like that as such. DC-10 is within within a walking distance or a short taxi ride also.
All the above just off personal experience. Others may say differently.
