I have used Comma oils for a number of years now. I was rather surprised to find that the Comma oil recommended for use in the T-jet was actually their blend designed for VAG PD diesel engines...
I've used Total Quartz INEO MC3 5W40 for the past couple of years and I can say it's definitely a decent oil. I've taken my car for a non-dealer service in the past where I'm convinced they've not used oil conforming to ACEA C3 spec and the difference is obvious.