My Stelvio ran great from new. The only thing I've done is upgrade it with new maps from Guzzi, so apparently they'd solved the lean-running problems in their control systems by then (2010).
Apparently California won't let you sell ANY vehicle there unless ALL the same specification vehicles are made the same way, so manufacturers cave in (since California is such a big market in the West, although not big compared to Asia) and make everything Cal-spec. The HEIGHT of stupidity is that anything from baby diapers to construction equipment that's sold in California must say "This Product Is Known To The State of California to Cause Cancer" if it's painted, has rubber parts, has almost any metal of any kind in it, etc.
They were the ones who started the thing where kids trail bikes couldn't be sold there because they had batteries with lead terminals, and they were afraid that the kids would gnaw on the terminals and get lead poisoning.
The "ruling elite" are getting so stupid and overweening that the rest of us are just starting to ignore them. Not a good situation for a functioning society, but if everyone (because they want to sell in California) buys into their idiocy out of greed, it's what we get in return.