There seem to be mainly negative opinions here about these cars, so I'll throw my positive one in: I think they're good cars ideally suited to racing.
1) They're relatively tough
2) They are fitted with low strength brown magnets, which are perfect for those who can't or won't learn to or don't like to drive cars that aren't welded to the track with modern mega strength neo magnets
3) Spares are plentiful and cheap
4) Complete cars are plentiful and cheap
5) They look quite nice, come in a variety of liveries and are a fair representation of the real cars
6) They perform well with the magnets removed
7) If you have a group of racers, some of whom like magnets and some who don't, keeping the brown magnet in is an acceptable compromise
8) The tyres respond well to a bit of sandpaper, even when they're years old, so there's no need for the expense of new tyres
1) They're not welded to the track with a high strength magnet, so will frighten and embarrass some drivers.
2) May possibly lack grip on Scalextric Sport track (I don't know, as I've not run them on it)
As to the chip or sell conundrum, I'd have thought it's two simple questions:
1) Do you need the money and/or space? Yes, sell. No, don't.
2) Do you or don't you want to race in digital format? If you do, fit chips, if you don't, don't.
Personally this thread has given me a great idea. I'd forgotten about these cars and hadn't driven mine for a couple of years, so I dusted one down and reminded myself that they're not half bad. In fact, they're a lot more than half good, so good that I'll probably buy a few more and use them as a class at the race meetings I run.
PS. You've got the Lucchini cars' rear wings fitted back to front...