Costco does a good job in their minilab. I have had no problems with film processing except that they do not process 120 film. When I have prints made, I have them made by the manager who I have gotten to know on a first name basis. If I do not like the print, he reprints it for free.
One time he told me to rescan a 120 negative because he was spots. I brought the new file in and he did not charge me for the redo.
The 35mm prints are made directly from the negative and even though they go through a hybrid process for up to 12x18 they come out better than if I had then make a CD.
For custom color I have an all optical photo finisher that I use.