ANY synthetic is far better (in many ways, explained below) then petroleum based oil, and overkill if you change it at petroleum based intervals. Therefore whichever brand you feel more comfortable with is better then ANY petroleum based oil.
Some interesting information about choosing motor oil;
Choosing the right oil - The oil companies provides “typical inspection data” to there distributors, and you get it from either. This data contains the actual physical and the common chemical properties of the oil. The most important properties to considering oil are, viscosity, viscosity index, flash point, pour point, percentage of sulfated ash, and percentage of zinc.
Grade/weight of oil – Viscosity (flowability) is how to measure the shear strength of a thin layer of oil. A bearing works by using a thin layer of oil not by the oil pressure generated by the pump. If you use too high a weight oil the layer will not form fully or may not get into the bearing at all. If you use too low a weight the layer will not give the bearing the proper protection. Bottom line, make sure you stay within the manufactures recommended ranges.
Multi viscosity oil is created by adding polymers (chemicals) to a base 5W, 10W, 20W. Think of a 20W – 50W as a 20 weight oil that will not thin more than a 50 weight when hot. Keep the weight range as narrow as possible. Polymers are prone to viscosity and thermal breakdown.
Viscosity Index – The Number indicating the rate of change in viscosity within a given temperature range. The higher the number, the lower the change. The higher the number the better. Important for bearings. Approx. range 110 to 210
Flash Point – Temperature oil gives vapors that can ignite. The higher the flash point the better. Approx. range 350 to 510
Pour Point – 5 degrees F above the point chilled oil will not move in testing. The lower the pour point the better.
Approx. range -80 to -10
Percentage of Sulfated Ash – How much solid material is left when the oil burns. The lower the better. Approx. range .5 to 2
Percentage of Zinc - Amount of zinc used as an extreme pressure, anti-wear additive. Zinc should be used when metal makes contact with metal. This should not occur. I try to stay away from any additives . High zinc content can cause deposits and plug fouling. If used in oil .11 would be the minimum effective percentage.
The pure synthetic oil is far superior to petroleum due to much higher temp. oxidation resistance, high film strength, very low tendency to form deposits, stable viscosity base, and low temp. flow rate. I recommend Amsoil and Mobil 1, testing and their data has proved to be among the best. I personally change the oil in my cars at 10K miles, 5K on my motorcycle, or 1 year, whichever comes first.
I have seen oil analysis reports on used synthetic oil with over 20K miles that show more protection left in it then petroleum based oil with 2K mile. The only problem is contamination. The longer the oil is used the more contaminants (combustion byproducts). These contaminants mix with moisture and create harmful acids. After reviewing this data I have come to the conclusion that one year is the point that i feel comfortable with leaving synthetic oil in a engine.
If your going to change your oil every 2 to 3K miles don't waste your money on synthetic oil. If you are going to keep your vehicle till it falls apart (like Me) I recommend using pure synthetic after your first change and following the manufactures recommended change intervals until the warranty runs out, then change it once a year or 10K miles whichever comes first.
By the way - You can mix synthetic and petroleum oil and can go back to either oil with no ill effects, Toyota's recommendation about not going back to petroleum oil really makes me wonder about all their recommendations.
Koz