Quick Question

One problem with Plarail Advance is that it uses the normal track system, meaning each train would have to be on one side of the track instead of in the center. If they made a smaller track system the same width as the grooves on normal track, it might have been able to work. Either that, or they could've added middle grooves to normal track pieces in order to make "solo" trains look better (therefore making the track "dual gauge"):

I actually think its a advantage that they did what they have. If they brought out dedicated 'single' tracks then to get anyone into Advance they would have to sell them a whole new track layout. Something not likely to happen if someone has a major investment in normal PlaRail. As for a new groove in the centre of the track this is a non-starter unless they change the connectors as otherwise the connectors will block the middle 'rail'.

Instead they gave you the option to firstly continue using your standard PlaRail track with minimal changes - you need special points, risers, stations and optionally 're-railer' tracks. But you could get away without these items if you absolutely had to and kept the track reasonably simple.

There is also the other big advantage that you can actually run two Advance trains on the same track side-by-side. Either in the same direction or opposite directions. If you had to have new dedicated track people would no doubt want this option some of the time, here you get it for free.

There is also the other way to look at this, Advance is the way to keep the younger child interested in trains as they grow older as they are more realistic and act as that all important stepping stone to TomyTec 'N' Gauge once they are old enough to appreciate them rather than just play/bash them