I had a few of those
some gliders, some with fairy-liquid soaked rubber band props for "take off".
I never like airfix, I never dabbled with more complex RC - but I loved those balsa-covered-in-paper machines.
I think it was the sense of 'building' you'd get. Small box. Simple stack of balsa sheets and ribbon struts (plus paper, bit of wire and a prop) - and if you put the time in, you made something incontrovertibly 3D and 'real' out of it.
Maybe it's the madelin-tinged-memory of sniffing those doping chemicals - but I'm not off to see if they're still available.