Additives and API ratings are more important than mineral vs synthetic.

Your dyno oil has the additive packages like those in Delo to keep pace with synthetic oils, Not all dyno oils do though. For example this is your typical additive packages. Additives: Additives are the different chemicals within the motor oils, which help oil and the engine to function properly. Additives usually include:

Anti-wear agents
Anti-foam agents
Anti-rust and corrosion agents
Oxidation Inhibitors
Extreme Pressure Additives
Viscosity Index Improver
Friction Modifiers
Pour Point Depressants


Here's the deal unless you have a high performance high horsepower engine you will see little difference. I would rather use a mineral oil with the Delo add package over SN RATED mobil 1 oil with only 800ppm zinc vs delo's 1500ppm.

And engines like old school diesels will do much better with the highest additive package possible. If your not doing extended drain intervals there really is no advantage.

Good little article that help explains it. Synthetic Vs. Mineral Motor Oil - Engine, Oil Tech - Hot Rod Magazine