There are several different Motul formulas. If it were my bike, I'd be curious which one they were using. I'm running Motul 300V 4T in our bikes.
No reason to worry between 10w and 15w in any ambient temperature you're likely to ride in. As for whether the Rotella will work acceptably for you, I'd let how the bike shifts be the determining factor.
No reason to worry between 10w and 15w in any ambient temperature you're likely to ride in. As for whether the Rotella will work acceptably for you, I'd let how the bike shifts be the determining factor.