Even though the oil looked good for at least another 1000km, or possibly more, it was the 5000km interval, so I've decided to take the trix (03 toyota Matrix) to the dealership for an oil change. Even after 150K clicks on it, it didn't burn a single drop of oil, so it deserved an dealership service, besides, the trix is the first car that I've truly loved, so I couldn't trust to those pirates who forgot to put in a new oil filter(!) again..
Long story short, it was a very pleasant experience, they quote you for an all-in price and in the end of the job you pay whatever you're qouted for, and to top of that, their prices, imho, are really reasonable. I've been quoted $97 for an auto trans fluid exchange, and $87 for the coolant exchange, including the parts, taxes and everything..
I don't think I'll go to an independent, or an franchise garage for the basic maintenance anymore, I think these guys got it right, as long as they don't screw this up, they got me, for the rest of my life.
By the way, it's been almost three months with the -new to me- Toyota Matrix, so far it's been Krown rust proofed, and got all of its fluids changed. It has the same driving perspective and utility of an CRV or RAV4, but drives like a car, so it has the best of the both worlds I guess, I really recommend it for budget used car buyers.