[Gordon Steadman]

When I designed my track, I did try and get the lane lengths near enough equal by having the same radius curves going in each direction with one crossover.

More of a problem is that the centre lane is quicker than the others as it has fewer of the tightest bends. However, as you say, if every lane is used during a race, it's not a huge problem. At home, it means that, as I generally run by myself, the centre gets used most and is well rubbered in but when guests arrive, the outer two lanes tend to be a bit slippery.