The bad: most airlines (especially budget) don’t give you enough room to use this

The problem is that these days, unless you're flying first class, there is simply not enough room for this to operate as it was intended.

I am 6 ft. tall and there just isn't enough room (even on a Qantas flight to Sydney Australia) to make use of it.

While I always have enough leg room (only 5’3’’), I can never get comfortable enough to sleep and if I do I always get swelling and leg pain (the seat bed is always too long so puts pressure on my knees)

I can't say the difference is dramatic (nothing can replace reasonable leg room!), but it's a substantial improvement, and you do feel it for sure.

There wasn't room enough to stretch my legs

Unless you are two feet tall, this won't work in economy on a plane as there is not enough room to have your feet hanging in front of you like that.

Sounds good but not enough room for it to function in coach.

Did not work; not enough room to put foot in if hung around tray

Not really enough room on Southwest plane to use

Unfortunately, there just isn't enough room in Economy to stretch your legs out like the picture indicates

Did not work; not enough room to put foot in if hung around tray

There is not enough leg room on planes to use this item