I purchased a pair of Caballo flats and they are the most uncomfortable shoes I've ever had!

I usually wear a 7.5 M but they were WAY too big - I couldn't even walk in them because there was a gap in the heel, and they flopped around. So I went a size down to a 7. Those pinched my toes and gave me a blister on my left heel. Sadly, they are unwearable because while they are super cute they so painful I couldn't even make it through a work day.