I confess at the onset that I am not an expert on the subject of GC but I do think I have a fair grip on the "interest" that surrounds this oil. Apparently, it is unlike it's other Syntec brethren in the fact that it is made in Germany and is supposed to have a PAO base. All others have the typical group 3 base. Also the first few years it had a green color and is rumored to smell like gummy-bears. It also seems to be getting more difficult to find becouse AZ is the only mass merchandizer in the US. Having said that let me share what I found in a AZ about 60mi from my home town. I went in becouse I had heard the 0W30 was on sale for 4.49qt which is good compared to most PAO oils. On the shelf the first 5 or so bottles were green labeled and said made in Germany on the back. The next 5 bottles were square-ish in shape and also said made in Germany on the back. The last 5 bottles were shaped like the first 5 except the label was yellow and white and said made in the US on the back. Now obviously the made in the US stuff isn't in high demand becouse apparently it is made with a predominance of group 3 base oil. Is this correct? If so,the demands can be met with a group 3 oil since it has the same specs as the "German" 0W30. Am I still correct at this point? If that is a fact how in the world can you be sure that every bottle of "German" 0W30 is actually a PAO based oil? The German bottles were just made in Germany but intended for the US market were they not? I heard that a sample was submitted to testing on this site some time ago and it seemed to be a PAO based sample. Whats to say a company that can obviously meet the specs with a group 3 oil would always use a PAO base in that oil? If the oil isn't being packaged for the German market would it matter if it wasn't PAO based? I am just asking questions becouse it's obvious Castrol can and will use a group 3 oil when they choose to do so and many follow the 0W30 relentlessly. Apart from testing every lot that comes from them, how does being made in Germany for the US market ensure the oil is PAO based? I'd say the group 3 based Syntec is a fine oil but there are alot of other oils made from the same base at mucho less money. What is written in stone that says all German bottled 0W30 has to be PAO oil? I am not being sarcastic; I just want to know what others here know that ensures them they are paying $6 a qt for real PAO oil. I apologize for the long post. Thanks for your help.