I bought a Pilates Performer machine many years ago and this has travelled with me to my move to Spain and back and is still going strong. Now mine might not be the most up to date Pilates machine but it works for me.
I was introduced to these machines when I saw one on a well-known shopping channel and they stressed the fact that while you exercise you are protecting your back at all times. As I have C4 disk degeneration I like to protect my upper back and neck as much as possible.
I find the exercises on the DVD are easy to work along with and apart from not lifting my head off the headrest during the abdominal exercises (to protect my dodgy neck) I do them all as stated without any problems at all.
For those that have never seen a Pilates machine you have four bungee cords and depending on which exercise you are doing you can have either one, two, three or four cords in use. The bench slides back and forth along the tracks and there is a bar at one end and headrest at the other. The two cords with the handles on are used when doing arm or leg exercises. The machine also folds in two when not in use and stands upright to take up less room.
Overall this is an integral part of my exercise routine as it is working out using resistance.