This is an excellent product. We've been using it for over 3 months and it shows no sign of wear or tear. It is constantly full of shoes which puts the top fixings under a tremendous amount of strain, but this hasn't damaged it. Each holder is big enough for a pair of normal shoes or trainers. For large boots (e.g. walking boots) it is easier to use one compartment per boot.
I am a size 7/8 (UK size) but have very thin ankles (9" circumference just above the ankle bone). I chose the "Small" size but it is still loose around my ankles and is therefore not providing the support I need. I would say the "Small needs at least a 10" ankle circumference to be useful.
For those who suffer with small ankles, I am able to create the required level of support by wrapping a crepe bandage in a figure of 8 around my ankle and foot. Takes time to do, but it does work!