do these really work?

The short answer is No!!
The curvature of the earth limits the range of VHF and UHF signals to less than 80 miles in most locations. I am quite well aware that there are exception to that. 150 miles is nothing more than a wild marketing claim.
From my reading and personal observation these antennas work better than I would expect, but for a very short period time. Normally less than six months when mounted outside.
The rotor in them often fails in a few days, and has no indoor read out as to which direction the antenna is pointed. The built in preamp is prone to both failure, and overload from nearby signals.
With some creativity on the mounting arrangement I think they would work quite well as an indoor antenna. Used outside they need to be replaced frequently.
I own one of these Chinese piece of junk antennas. I have it mounted in my attic. It works well enough, but it's pretty clear the VHF-hi balun has lost sensitivity, so I'm not picking up NBC (RF channel 10), and UHF sensitivity is dropping over time. It's my intention to replace it soon, once my medical bills from last fall are paid.

No, it will never pick up anything from 150 miles away, but it does have surprisingly good reception on UHF as long as you have line-of-sight to the tower, or are somewhat closer on 1-edge and 2-edge stations. However, low-power stations, even nearby ones that should have better signal that distant high-power broadcasters, are choppy and frequently drop out.

I used to recommend this one when I first bought it, but after 2 1/2 years with it I'm a lot less satisfied.