Both.
If I had to choose 1 it would definitely be Musicman.
Why.
I'll tell you.
I love them both. Currently own 2 Warwicks (a Fortress One and a Flashback), have owned 2 streamers and a Corvette. I also own a Big Al, a Stingray, A Bongo and a Sterling.
What I like about Warwicks are the unmistakable growl, and just the pure gnarliness of their tone. I also like that they seem indestructable to me. I'm a wenge neck fan, and I never have to adjust the necks on my warwicks. I just did a short tour with the Fortress one, and I didn't even have to tune it before gigs. Seems rock solid all around. All my Warwicks also have/had great action. For whatever reason they seem to be able to go lower than other basses, at least all of the ones I've owned.
What I don't like about them is the fact that in comparison to MMs, and despite the people who will argue vehemently, they all seem like one trick ponies. They get a great ballsy sound, and it's tweakable. But that's it. And one of my streamers was a jazzman. I've said before, and almost made a video comparison which I'm so sorry I didn't, that it seems the warwicks tone controls go from 1 to 4, while the musicmans go from 1 to 12. There is soooooooo much more variation in the tones I can get on a MM as compared to that on a Warwick, and I love versatility.
Other thing thing that saddens me about Warwick are the ridiculous prices, and even more ridiculous resale values. My first Warwick I bought new (nobody knew what a Warwick was then), but I'd never do that again. I think Musicmans are very reasonably priced.
Someone was talking to me and I lost where I was here

.... anyhow, I like MMs more for lots of reasons. I like the way they feel more, I like the way they look, they're usually lighter, and as I already mentioned - the versatility is staggering in comparison to warwicks. Which is probably my #1 reason. And if anyone thinks the endorsement thing taints my opinion, when I got that endorsement I was in a place where I could have just as easily gotten a Warwick endorsement. I owned a Sterling, and a Bongo at the time, and that's all I was playing. Big Al is now the bass for me, and I'm really getting the feeling that nothing is going to ever outdo that bass. At least for me.