This is a nice little sling.

The soft sling is not ideal, since your legs tend to bunch up together.

The soft sling is not ideal, since your legs tend to bunch up together.

The strap needs to be able to take up about 3 more inches to suspend the sling to support your legs and it just doesn't.

I've also used an inflatable footrest and find that this sling has the advantage of being usable even if you have a bag stowed in your under seat space