Yeah, the tank-bus is definitely a barrensmobile; you can kind of wait and see on it. If you do end up seeing situations where you could have used it with decent frequency, it is IMO the best barrensmobile for price::value. If you don't, I still recommend a Roadmaster with a concealed turret for a psuedo-tank that looks legal; keep in mind they get used for all sorts of stuff like transporting valuables, VIPs, etc, so it's not like one of them says "strike team incoming" like, say, a Citymaster does.
30F means the Command 10 program will take some looking, but it is so very worth it.