I bought Winsor Pilates a few months ago when I couldn’t get to classes due to location, and loved it right away. I didn’t think it was going to be much of a workout, but if you really concentrate on your form it’s great for toning and flexibility. You also progress fairly fast. A good mat is crucial so you don’t injure your back or spine, but the tapes are pretty user-friendly, and I didn’t really have any problems with injury or pain. The downside? After about a month and a half you get pretty sick of the tapes. Now that I’ve been doing it for awhile, I just use the winsor dozen (A pamphlet showing a sequence of moves) and skip the tapes altogether. I switch it around, focusing on legs one day and abs the next. It’s much more relaxing with music instead of Mari constantly telling you to “pull your belly-button towards the spine.”
Ladybug, the tapes do have a person showing you how to modify the moves at all times for people with back or flexibility problems. I had to use it alot during the beginning, but I noticed that unless you really focus on controlling your muscles and posture, you don’t get as intense of an experience. I’ve also noticed that most Yoga and Pilates tapes/systems have a modifier, so it shouldn’t be too hard to find one that works for you.