The one with the studs definitely has more personality than the first one. Not sure what the anatomy of the inside looks like or if the closures are the same, but that's also something to consider. You can dress up #2 more? I'd go with that one!
I love the first one - I had the same dilemma. I went for the plain (but in grey) as I had been looking for a small special grey bag for ages. Depends what your after - if you want something more classic go for the plain but if you are after something a bit more edgy try the studded one!