I purchased this bag in the large size. It seems to be about the same size as the large Veneta, but it is more slouchy due to the softness of the leather. The "studs" are made of a silicon gel, and while the SA explained the process of how the effect was created, I can't remember the details.
The bag comes in three sizes and for me, the large was perfect as the smallest seemed really tiny and the maxi was overwhelming on me. I am a bit concerned that the leather will scratch, especially after seeing a bag on the floor at Saks that already had a few marks. The SA swore that they would rub out but I'm not convinced. I haven't used my bag yet, but I've tried it with several things and the style seems to go with everything. Looks great with super casual stuff and work clothes too.
I hope this helps. Here's a pic to show size--