I'm due for an oil change very soon. Last time I took it to a Mobil Oil change place and they charged me 65 for synthetic oil (Mobil 5w30). The tech there then recommended I get a "synthetic" filter instead of a standard one (10 bucks more). I asked if the standard one would work and he said yes, but the synthetic one is better suited. I was wondering if I got ripped off by paying 75... thx