In my opinion, an acoustic bass guitar is an incredibly niche instrument when it comes to gigging and recording. Many a bass player has one gathering dust in the corner of their practice room but it's a great instrument!
In nearly 20 years as a working bassist, I've probably used an acoustic bass guitar once, maybe twice. Most of my gigs are loud, electric, and in need of an amp plus electric bass.
You can use them for gigs though:
They have a tone that no other electric bass can match (although basses equipped with piezo pickups can get close) and if you're planning on unplugged-style gigs, very quiet acoustic music or similar then check them out.
Where they come into their own - in my opinion - is as a practice/ideas/composition instrument. You don't need to plug it in, you can hear it when you play it, and it's a little more difficult to play. It's easy to get practising with one and it will also hep you build your technique.
If you get an electro acoustic one, you'll need an ultra high impedance DI, something like this. In terms of instruments, there are many options and, as usual, try before you buy.
I have a Breedlove acoustic bass guitar and I love it.
