I usually bring two. One is almost always my Lakland 4-94. It fits the music of the band I'm playing with very well and damn, it's just awesome. I rotate the second amongst my Fenders, Gibsons, Alembics, Musicmans, Pedulla, Sadowsky, etc. Last week I took my Pedulla and my Lakland, and both worked very well indeed. The Alembics I'm more judicious about - they are a very precise tool, and not every venue I play lends itself to that unfortunately.
I tend to play one set with one bass, the next with another, etc. I soundcheck both, the soundguy knows how to eq them. I also run the direct out on my Alembic F1-X preamp pre-eq into the board so the sound guy can get it where he wants it. I've had no complaints yet, and most of them praise the DI on the F1-X. I keep my effects use to a minimum too.
I have brought three basses to a gig on occasion, but that's the exception rather than the rule.
Alan