I wouldn't have any issues providing info to a band, assuming they are credible (as you stated, active working band, gigs booked, etc). Start ups are usually not anything worth while, for me at any rate ....
That said, most of the working bands in this area rarely advertise for players. Slots are usually filled through networking, word of mouth and interaction with a bunch of other players. I have started a new funk/R&B band as a side project and didn't have to resort to ads to get the requisite players .... all word of mouth.
A lot of dreamers out there without a game plan, so expect to waste a good amount of time when responding to blind ads ...
