I think they're these, right?
http://x3ap.roguey.co.uk/ships/class-M7C/
Anyway, I've never really used carriers so far, my style is more rambo type, I go attack alone without having to worry about commanding other ships except when I call just one ship and tackle something in tandem. Apart for the prototype unique ships I stored in my griffon, I don't even have any small ships in my fleet.
Though I might get one eventually just to see how it is and mix things up a bit. Too bad they're not as maneuvrable as I would hope. It's a pain turning my cobra around, and these aren't much better.
Oh, and also only two of the five have reasonably more hangar capacity than a cerberus... which is a full on M7 with all the benefits like shielding, maneuvrability, firepower etc. And one of the two is the griffon hauler which we can't get.