True, but it costs a fortune to ship along with a high price tag to begin with. I also must say that while i cannot verify this, (then again who can really verify anything when it comes to oil) but it's been reported that amsoil's viscosity breaks down within something like 50 miles, so that for example 20w50 would break down from 50 Wt to 30 or 40 Wt. On the other hand, it's also been reported M1 bike oils have since the formula changed a while back been reported to do just the opposite. It's said thier 20w50 goes up to 60 over time. I may try the 10/40 next time because of that. I would also go with 20W50 if i used amsoil so that in case thgis is true it would retain a reasonable viscosity.
This is all from things i read online, mostly if not all at a motor oil forum. True or not, whenever there is no way to get a definitive answer i always err on the safe side. I doubt amsoil could ever be considered a bad oil, so i still recommend it. But like I said, they are both good so i err on the safe side and in the process save money and can get it locally .