It is not better than M1 10w-30. However, I use Castrol GTX 10w-30 in my '94 Taurus SHO (Redline is 7,300 - and it does see it often). I just change the oil every 3k miles and use an oversize oil filter and roll with it.
Not really fair to compare it against Mobil 1 as was mentioned. But for frequent oil changes (with no abnormal conditions)- it will yield results equal to Mobil 1. Once you push it beyond 4K all bets are off. Also with lots of high rpms it's possible to shear down (become thinner)- in as little as 3K miles.
Check Used Oil Analysis (UOA) here: