Paul, this is such an excellent thread! Many thanks for all the info provided and the pics.
The U5096 is one of my favourites. When my parents split up in 97, my Dad bought one of these second hand, so I have very fond memories of it. Unfortunately, when he moved in with his then girlfriend in 99, he left it behind in his old flat in favour of her grey Turbo 2 Autosense. Foolish man!
I have some very fond memories behind a lot of these cleaners - some of which I haven't seen in 15 years. The basic red TP U2724 was certainly a blast from the past. A friend of mine from school who lived in a block of flats up the road from us had one of these, but I've not seen one since. I don't suppose they were particularly popular, not being much cheaper than the U2798 and, of course, on-board tools being "the thing to have" of the day.
Again, big thank you for your effort with this thread - it's fantastic that we have resources and references like this preserved online to turn to when we need them