At my doctor's suggestion, I purchased the McKenzie book and the McKenzie Lumbar Roll - Firm Density. I used a rolled up towel until the McKenzie Roll arrived. I tried my one hour commute to work with and without the McKenzie Roll. Conclusion: The McKenzie Roll is dramatically effective for me; I would even say amazing. A rolled up towel of the same size is too firm, particularly in my vehicle seat. After experimenting, I now do not strap the roll to the seatback; it is easier to just position the roll after sitting in the seat as instructed. It is important to "roll" the roll into the correct spot on your back; too high or too low greatly reduces the effectiveness. It does take some getting used to, but it is well worth the effort. I now find I forget it is there after ten minutes or so. I started to cut off the strap, but then I found it is handy for attaching the roll to the outside of my computer bag to take on the airplane. I also tried the D-shaped roll, but I like the round one better; it is easier to roll into just the right position. I think the McKenzie exercises are also important. They are easy and don't take much time; however, I think they must be performed exactly as instructed in the book to be effective.
Rating: [5 of 5 Stars!]