I've long been sitting on switch accessible Scalextric, but I'm finally very close to having a D.I.Y. guide ready to go up on-line. The nice thing about modern 'Sport' Scalextric is that with a pair of variable power supplies, you can adjust the speed of both cars to suit the abilities of the player. Magnetic cars prevent the cars constantly flying off the tracks which is handy too.
There's also two ways to play using a single switch - Full Speed On/Off or Coast/Boost mode. More to come soon. Meanwhile you can view another YouTube video here.