Well not actually a Scalextric car, but Squeezie himself nominated an Exin car, so, Revell Aston DB5 when I was a kid and probably SCX M3 when I became a club racer.
The Aston(s, my dad bought one for himself and one for me) came along after we had been running Scalextric and Airfix cars on the circuit in my sig pic for a few years and once we had them the home grown cars got used mostly as scenics. They were a total revelation compared to the old pin guide RX powered cars and the troublesome Formula Juniors. The handling and speed were awesome and they made a great "racy" sound. Not sure where Dad would have got them then, possibly a whim purchase at somewhere like Beatties of Holborn, but I suspect partly inspired by his 1/1 "toy" which can just be seen in my sig pic too
When I started club racing in the early 90s, there was a structured Thursday night club and a less fixed Tuesday session. Basically on a Tuesday everybody would bring along cars they fancied thrashing round and we'd all peer in each others boxes and decide on 6 classes to race. SCX M3s were probably the nearest thing to a permanent fixture, nobody ever said "Oh no, not them again". Probably because they just produced some fantastic close racing between competitors of all ages and capabilities. Mind you all of the SCX cars of the time were great- Squeezies Ferrari and the other F1s, the GT cars BMW M1, Porsche 911/935 ,Ferrari GTO/F40 and of course the rally cars RS200, Quattros, Celicas and 959s. the nearest Scalextric UK cars were the GroupC LeMans cars.
Mr.M
P.S. Still got all my cars from my childhood (Thanks to Mum & Dad) and am still hooked enough to have approaching 2000 more