I've been looking at these boards and I am now coming to a decision. What is better for me? The auto is an 89 Acura Legend with approx 250,000 km. The engine runs well and is in good condition - still smooth and pulls strongly. I want to keep this car another 5 years or another 100,000km at least. I've owned it since 1992 and it has been good to me. Between 94 and 99 I used Esso Synthetic (real PAO?). In the last three years, it's had GTX, Syntec, Tech2000 and Pennzoil. Usually it got the 3 month or 5,000 km deal. I just replaced a couple of side valve cover gaskets and the distributor o-ring because of oil leaks. So I think my seals are good now. But I noticed a bit of varnish on the covers and there has been some buildup on the PCV ( after 12 years I replaced the valve but it was still functional) but I did not detect sludge. It looks like it burns about 1/2 quart every 4000 -5,000 km. I am interested in using the German 0w-30 Syntec and I think seepage is less likely a problem with this oil since it looks like it remains "thick". Plus the A3 rating will allow peace of mind with an extended drain. I'll also use an oversized Honda NSX filter for the extended drain. Intended drain 6 months at which time I also drain my ATF with Honda ATFZ1. It costs the same to change the oil twice as often with Castrol GTX 5w-30 with a Fram or Purolator filter. Intended drain 3 mos. The car is driven mainly on short trips now with some highway 20% of the time. Would the 0w-30 Syntec keep my engine and lifters clean? Most Legends start having lifter noise from being gummed up later in life. Also wouldn't those esters in Castrol Syntec 0w-30 help with my valve stem seals? Sorry for long post but you need background.