This cold air thing works well in high performance applications & at higher engine speeds, but if you are likely to spend much time at slow speeds, in cold areas, particularly if the humidity is high, like in fog & mist, then you will want all the heat that you can get to stop carb icing, & the need for rich mixtures, which in turn tend to wash the oil from the cylinder walls, which then in turn leads to accelerated bore wear.

You get nothing for nothing.