Watts, "I suspect their idea of customer service won't match Lexus." Ha-ha
"Metal valves aren't necessary." Ok noted. I won't bother then, thanks.
"Another option to look at is Costco, ... "
Yes, I've seen good reports about them too including they are careful when fitting, if asked nicely!
I think you have to pay a membership fee, but that could still be cost effective I know.
Our nearest one is about 40 miles away but I'll still contact them for prices.
Peter