I just bought the Saffiano Cuir tote with black exterior and red interior. I got the large and it comes with a strap. I then went online and saw people saying only the medium has strap. Did Prada change their size recently? I did saw 3 different sizes at the store so I'm sure mine is the largest size. The other thing is after putting my normal items into the bag, I found it to be quite heavy. Anyone has similar concerns?