so long as the oil is changed frequently and regularly, synth or not, you ought to be fine. even with the hotter M119. However, if you drive the car hard during the interval, then yes, you would benefit from going to a synth...or, you could just change more frequently.
synth is used in racing because of the extreme stresses that are placed on the engines. 18,000 rpm for a v-10 in F1
but they don't have the opportunity to change the oil at a pit stop, so they need something that won't break down.
As a "regular" driver, i, personally, can't justify spending 2x as much for oil i'm going to drain out at 3,000 mi anyways. Dino oil works fine up to that point and is cheaper
just my position on the whole issue.
if you prefer synth, by all means, load 'er up