Re: Group 1 car seat for GT???
Maxi Cosi Tobi is a very nice seat, but looks HUUGE in the GT. Although it isn't on the 'approved' list for the Gt, we opted for the Britax duo iso fix seat. It fits really well, and in fact was the only one that I was happy with the fit. The Toby (in my humble opinion) didn't fit in as securely.
It seems that Alfa wouldn't cooperate with the seat manufacturers at the time, so no seat were tested, hence thay don't show up on any list.
Your kids are the most precious things, so you have to go with what's right for you. We spend weeks trying to find a seat that fitted, and could only find one that we were happy with. Buckle crunch is a big issue with the Gt as the seat belt anchors are longer than most cars, which is why we opted for an isofix seat, even though no manufacturer listed the GT as 'approved'.
Good luck with the search