Mostly depends on a persons(shops) mechanical ability. Also somewhat on what assorted tools one has at ones disposal (small shops might not have specialized tools for latest models).
Personally, I never go to the dealer unless it is beyond my ability or a warranty issue. Oil changes, belts, hoses, wipers, brakes, and the like, are all things I'd do myself before I'd pay a dealer. I have not had good experiences with dealers, although I am sure many are well equipped and have good technicians. There are others that hire the cheapest labor they can find, an use your car issues to train their technicians,
I paid enough to my last Kia dealer service dept.(to have them attempt to fix my Rio) to have purchased my own computer diagnostic equipment, and am still irritated that I didn't. I had a Dodge dealer charge me for silly repairs that weren't even done, AND left the air filter assembly and PCV hose OFF when I went to pick it up from service.
I think you'll save money going to an independent shop, but check and see that they have access to the service info and know something about your particular model. Newest models may be best left to dealers because they have best access to latest information and lines of communication to the manufacturer.
If you can handle it, do as much as you can YOURSELF, and skip both the dealer and the independent shop.
My car is still under warranty so I take it back to the dealer.
With my old 2001 Kia Rio... I took it to Crappy Tire for an oil change and 2 hours later the engine seized up and the motor was ruined.
Crappy Tire stepped up to the plate and replaced the engine at their cost, however it has taught me to beware of where I should take my car to be serviced.
So my Kia dealership is my place of choice for car maintenance.