I dont know enough about tires to gamble personaly Ill stay with Metz when the change comes . Ill let the trail blazers test anything else.
To me a bike isnt like a car in this respect and my personal thought is its dangerous enough on a bike for me to dick about with stuff I know nothing about. I suggest if you are also someone who knows little about such things you leave well alone and stick with whats recomended for the bike.
Changing every season regardless? Are you barmey hehehe. Change the tires when they need to be changed.