It depends on the target tradeoffs.

4 wheels can be inherently statically stable but requires more space and requires more energy when running (counter-intuitive, but if your balance algorithm is efficient, you use less energy wheeling around on 2 than on 4 because you can basically play games with gravity to get some acceleration tradeoffs... And you have half the number of powered wheels, assuming you're 4-wheel drive).

If they solve the hard math, the end result may very well be a more performant machine (though as someone else in thread has noted, depending on the overall goals, a zero-wheels statically-mounted arm could be better still).