Tobie, the trad wool is obviously heavier, a bit less comfortable than PV, but also much warmer for very cold weather (not that I even know "very cold" here).

The USA kilt will be nicer to sit in, esp. in a motor, the thick kilt is a challenge to arrange properly when driving.

I've yet to see how warm it is in cooler weather, it's pretty cool here now (about 9-10 celcius). When I get to wear it outside I'll tell you more.