It is still valid as a place to start in your own search. The formulation of oils is constantly being updated and subject to change by the manufacturer at any time. All Oils are 20W-50W Brand Visc. All Oils are 10W-30W Brand Visc. The synthetics offer the only truly significant differences, due to their superior high temperature oxidation resistance, high film strength, very low tendancy to form deposits, stable viscosity base, and low temperature flow characteristics.
Synthetics are superior lubricants compared to traditional petroleum oils.
You will have to decide if their high cost is justifed in your application. Synthetics can be run two to three times the mileage of petroleum oils with no problems. They do not react to combustion and combustion by-products to the extent that the dead dinosaur juice does. The longer drain intervals possible help take the bite out of the higher cost of the synthetics. If your ATV or bike is still under warranty you will have to stick to the recommended drain intervals.