For basic tracks and formed flat areas Quads are fine - it's only when you get to slippery or steep (or fast as F boi) that they can bite you in the arse and quick. Square geometry (as wide as long for most of them) makes them inherently less stable than most people think - same category as the little Suzi Jimnys and the like to be fair. Having said that, I've seen a couple of cockups with SxS's that really had potential, and it was pure luck that no one got seriously injured or ended.
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