I don't really have time at the moment to do photo comparisons, I'm going back and from hospital visiting my dad, but I can say the Cindy holds a lot more than the mini Selma. It would hold a similar amount to the medium Selma messenger but it is a tighter fit. There is detailed comparison of what the medium Selma messenger and Cindy can hold in the Cindy thread which might help a bit. I can post a comparison with the mini over the weekend if you still want it. I would choose the Cindy for day to day shopping and going out for a meal whereas I think the mini Selma is too small for shopping but perfect for a night out.
I agree with everything MKbaglover stated. I own all three of the bags. I posted a comparison of Med Selma Messenger vs Cindy crossbody in the Cindy thread. Mini Selma definitely holds a lot less.
Thankyou for your responses. BeachBagGal, I have seen the size comparison post in the cindy thread. Thank you, it's great help. I went ahead and purchased the steel blue cindy crossbody. I hope I like it as much as MKbaglover. MKbaglover, I hope and pray your father gets healthy soon. Ox