[Perfectlap]

vs. going to my independent mechanic, I don't find it all that cheaper to DIY since I'm not buying Mobil 1 and stopped doing so once the car hit 50K miles.
And going forward as the engine gets older, I'll be protecting it with more expensive fill (Motul, Redline, JG, etc.). I'll also be adding the spin on filter which they don't give away for free with every 5 quart jug. My mechanic doesn't make money on the oil/filter, I usually provide. So I'm paying $20-$30 for the convenience, and generally I have the oil changed when other things are being worked on in their shop.

I'd say the advantage to DIY is that you can drain the oil overnight and get out all the old stuff.
The dealer or mechanic will only let it drain for an hour or so.