If given the choice of a DI or mic, I'd ideally take both, or just use a mic.
For a 4 string bass amp mic, a Shure SM57 works just fine for me but I also like my EV N/D868. I usually carry one of the above mics and my Sansamp Bass Driver DI to all gigs.
But, most sound techs only have 1 channel available for bass and prefer a DI over a mic. 90% of the time, they'll use the Sansamp when I offer it. Every once in a while, you run into a guy who just isn't comfortable using other people's gear or trying something new. I'll just grin and bear using whatever they want. Never pays to antagonize the sound techs and maybe next time, he'll be a little more experienced or open to your suggestions.