I've been using a set since the local gym closed four weeks ago. Since I don't yet have a door anchor, I had to be a little creative, but I can replicate all but two of the exercises I do in the gym. I can't replicate the spider curl and the Callahan press. The resistance curve is different than dumbbells, but if you use them correctly, you can get in an excellent workout. If there is resistance at the beginning of the rep, you will have good resistance during the entire concentric and eccentric phases, just do the rep slowly both ways and hold for a second or two at the top of the rep. If you have the type where you can clip multiple bands to a single handle, you can load it to the point that you cannot stretch them.
After watching the video, what I'm using are lengths of tubes with a handle at each end instead of bands.