I have been using Silkolene Pro-S 10w/50 for a while and am now thinking of trying Motul 300v Competition 15w/50. I'm an 'oil novice' and just fancy a change for the helluvit! The car has a Rover 620ti engine, hybrid turbo with roller bearing, runs about 275bhp and 280lbft torque with forged pistons and is used for 'road fun' without ever being coshed on the track. Is there a really worthwhile benefit? Best protection is main priority but all of these fully synth. oils of today seem so good. Only 'set in stone' spec is that it must be ester-based or the turbo warranty is invalid. TIA.