MS3 Dealer Oil Change Problem

It appears that the information that the dealer uses, some online service manual, actually shows 5w-20 oil for the MS3 instead of the 5w-30 that the manual recommends.  My wife caught it in the paperwork yesterday and made the swap the oil again.  I spoke with the service manager today and he agreed that it should be 5w-30 for all of the Mazda turbo engines and that was the only reason they had something other than 5w-20 oil.  Interestingly enough, he mentioned that he thought that 5w-20 wasn't as good as 5w-30 in any engine.  It is recommended based on mph alone.  Just an FYI if you take your car to the dealer and want to make sure you are getting the oil you want.

The link below supports what you have heard. 
 
I am not a fan of 5w20, and have been using 5w30 in my M3 (not a speed).  Did a bit of research, for the 2.0 engine, in most of the world, Mazda recommends 5w30.
 
http://bestsyntheticoil.com/dealers/amsoil/5w20-cafe.shtml