To me it's really obvious that your friend should get a Squier P Bass. I am a Ric player these days (used own MM and Fender stuff as well, still GAS over MM occasionally), but frankly I think it would be bad for your friend to start with a Ric *unless* he can find a good used one for the cheap (CL > eBay) *and* has a close friend that has been playing Ric basses for several years and does their own setups. You see, Ric basses, while not actually being any harder to maintenance, are just different enough from the run-of-the-mill stuff that most people on a forum such as this aren't going to be able to give your friend proper advice in the event that you want to, say, adjust the truss rods (there are two). How many people here know that Ric truss rods only act in one direction (front-to-back) and not also torsionally like is commonly rumored? It's easy to get erroneous "info" about Rics and that's why I think they're dangerous for a newb.
Squier P or PJ is your best way to go... as for the "best bass", it's what your friend likes the best--and his taste will change with time. I started out on a Spector and now I find them pretty blah, just as an example. I did enjoy it at the time.
I'm surprised how many people who replied think they know what "the best bass" is. You give yourselves away when you say it's not on that list. Honestly, if Jaco or Jamerson walked up to most of us with an SX bass they could probably wipe the floor with us. It's about finding the instrument that you enjoy working with, not finding "the best" one, because such a thing doesn't exist. We have to make that clear from the outset.
Since so many people were wondering my friend is willing to spend $1500 at the most. 
