Besides the 40wt part I mean, thinking of (for new new Japanese Mazda Miata ride w/1.8 DOHC), possibly squeezing better mileage/start up protection w/ M1 OW-30 vs 5W or 10W? I know the OW-40 is thought of highly here (and I'll use it w/ my 9500 mile LT1 powered Impala SS)...the Miata is usually "short trips", 6K miles or less annually, with temps rarely (sometimes) below freezing and rarely (sometimes) above 90'F..
got some $3.99 M1 coupons to use so I want to get a couple cases thsi weekend of either Ow-30/5w-30 or 10W-30 for the Miata...??