I have experimented with it three times. The first was due to my own curiosity. The next two times was because the Dommme said she liked doing it. Like all painful activities it has different intensity levels. In all three instances my experience was at one of the lower (but not lowest) levels. I would suggest starting at the low/moderate level and work your way up.

Yes it can cause trouble walking and if the Domme doesn't know what she is doing can require medical attention afterwards. I found it interesting as something different but not something I wanted to do very often.