See, theres this thing called "research"
I understood fully and completely that once I chose my Grand Company,I would not be able to look back. this left me at the deciding quest for about 2 days while I weighed my options.
I looked at the gear each had available, I looked at each bird's Barding, and I even checked within my LS and household to see which Grand Companies they were in.
In the End, Kan-E-Senna's light show and the Crested Barding from Gridania won me over, however that could have easily been changed had my household members chosen something like the Maelstrom. I would have gone with that, instead.
I agree with Asi. They made sure that, unless you rushed through everything without reading, you had all the information you would need, PLUS ample time to weigh out your decision. I mean, you joined a Grand Company, which means you spent a good deal of time running around.. during this time, you didn't bother to ask your friends "So which GC are you in? I think I like these guys" OR to look up on Google your companies barding?
Gonna sound mean here, but it sounds like you made a hasty decision and now regret it. use this experience as alearning tool to not make the same mistake again.
... Besides, once Dalamund falls, I don't think your GC will matter.
EDIT:
My apologies, I was under the impression that the Barding and the like had been around for as long as the companies themselves. My LS member just told me the Barding is still fairly new.
Sorry for sounding like a douche.