I think these machines are pretty good for what they are, I think the automatic height adjustment works depending on the pile of the carpet. I think for the lower pile carpets, Berber or patterned carpet like yours they do fine on, however thicker carpets like deeper pile shag carpets it will probably struggle with but that's just my theory. great video 🙂

I had a Windsor Sensor XP12, which was nothing more than a commercial version of the X4, and I did like the idea of the electronic carpet height adjustment, but for the carpet I had (medium pile shag), it just didn't dig that deep into the pile. I still don't think it's a terrible vacuum though, I just now think there's certain piles of carpet that these don't dig the deepest in the carpet (unless it's a later model with the boost feature).

On these I think the auto adjustment spends more time going up and down than cleaning the carpet.. just my two cents