Like I said, it's great for my Hondas. Matter of fact, for most automotive applications, I would recommend the SuperTech oils, as they're a fine value. It's all about using the fluids that meet the manufacturer's specifications. The SuperTech synthetic oils exceed the specifications that my Hondas take, and the price is good. Turns out that the 5-speed manual transmission in those cars call for 10W-30 regular motor oil. Yep, seriously, that's what the Honda Owner's Manual says (I still have it). Therefore, I use 10W-30 synthetic (SuperTech), which is even better, and I change it at the specified intervals.
Likewise, for the Mercedes-Benz, you likewise should use the fluids that meet the manufacturer's specifications. In the case of the M112 and M113 engines, that means the 229.5 specification. There are several motor oils out there that meet that; SuperTech is not, unfortunately, one of them. So, for my Benzes, I use Mobil-1 FS European Formula 0W-40, which does meet the spec. Really, folks, it ain't that much more money, especially when Walmart has the "rollback" prices. That's when I stock up.
Same goes for oil filters. For my Mercedes-Benz M113 engines, I use only the OE fleece filters, because they're the best *for that engine*. For my Hondas, I use Fram or Purolator, purchased from Walmart.
Stick to the spec, folks, and you generally won't go wrong.