Hi and welcome, I am new as well, and by no means an expert! I asked the same question here, too. I bought a city for my first bbag b/c it seemed like a great option size wise, plus it can be wor several ways, including having a strap. That being said, I have just ordered a GH part time, similar to a city, just a different shape and a slightly longer strap. So, I guess it depends roughly on your preference for a strap or not. For me, I wanted a strap, plus I really love the size and look! Good luck.
I have learned thru trial and error that I am a City girl!!! The size and shape is just ME!
While I love the LOOK of the Brief and did purchase one, I felt I was just too short too carry it ... so sadly it went back.
I first got the First, then the City and then the Purse. I would recommend every single one for different reasons:The First is just so pretty and the classic BBag IMO. It is a little small which is why I got the City which is perfect in size for every day and also very pretty. The Purse turned out to be my favourite style because it sits so comfortably under my arm and looks so feminine and the size is just perfect for my needs- oh, and of course I think it's very pretty, too!
So you cn't go wrong IMO and I'm sure you'll be back for more soon anyway!