H.O. scale is what I had too. The basement at our farm was dark and dirty but it had room for a 4' X 8' layout. It was one of my hideaways when I was young. - That and playing with my little green and gray army men outside.
These lager scale tracks seem more realistic as far as speed is concerned. If I really wanted to splurge though, I'd have gotten a digital track. I didn't even know they existed until after I started putting this one together. On them you can run 6 cars at the same time on a 2-lane track. All the cars are still individually controlled and the track has lane switching sections where you can choose whether or not to change lanes for passing. If you set up a 4 lane track you could run 12 cars simultaneously. - An 8 lane track could run 24 cars at the same time!
They have all sorts of other features as well. You can set up the tracks with pit lanes and you can program it so that you need to stop and refuel. They calculate fuel consumption based on speed and you can calibrate the rate they use it up.
They also have the ability to run computer controlled cars to compete with and have towers that track & display the order of the leading cars. They also have rechargeable wireless controllers as an option.
The digital tracks are the way to go. I guess it is possible to convert mine to digital some day but it wouldn't be cheap if I got all the bells & whistles to go with it.