I have one of those, and its great
The bottom of the chair actually has little leg things that can be pushed out, to give them more height if they are strapped into a chair. The best thing I find with it is you can pull release the tray with one hand.
Its been invaluable really. Great for sitting him outdoors with us, great for taking to my parents for dinner, and really easy to clean. Theres no little creases that crumbs get stuck in,