I love Zumba!  My 59 year old knees didn't like the twists, though, so I looked for some shoes that offered support without the 'grip' my usual workout shoes have.  I do Zumba at my Curves Fitness Center, so its on a carpeted floor in between the circuit machines.  These shoes are awesome.  The fit is snug, I did order a 1/2 size larger than my normal, but they do stretch some and the best part is that my shoes are not giving me a pain in the knee any longer.