Well, you will want it for each time you deploy as a rule.
One of my favorite designs is the Blizzard Hover APC- 9/14 speed, 6t of cargo space, and a LRM5 in a turret to throw smoke at a pretty good BV. Armor is beer can levels, but that is the trade off- not sure even FF would improve it much- with a ICE engine so you have some logistical concerns. The Jihad era Saxon is better, 10/15 with 5t cargo though its weapon choice is worse (MG), and I think it has more armor with a FCE for a bit better logistics burden. Of course, Omnis are also a great option Epona, Hephastus, Owens, Manteuffel, or even Bolla when covering a road are pretty good.
For me BA transport is about the speed to get it into position- be it in BV balanced scenarios or campaign . . . with that said, in my campaign that has really used BA & transports are limited to what is on the open market and timeline. I really really want a couple of Main Gauche IFVs, if I ever get heavy or assault firing platforms like Grenadiers then a specialist Prowler would be a great for what it can offer- amphib, LRM support and electronics.