I have the Speedy and I'm now looking at the Trevi.. I think the Speedy you can have and use everyday to almost every outfit! It can be very casual but also look very classic and nice. The Speedy bag also holds a lot of stuff very easily. The Trevi I think it's harder to make it look as casual as the Speedy. For everyday use I would say the Speedy, but I really love the Trevi as well, it's so beautiful. But I assure you, it won't be your last LV bag, so maybe you can buy the other one later on as well?