Well, some Photoshop effects are quite realistic looking. I used it to color a drawing that I did and it didn't look like CG, it looked like it had been painted with watercolors (which is how I generally color my drawings anyway). But in general, I'm horrid at actually coloring things in Photoshop, and adding PS effects to drawings generally doesn't look too great unless they're subtle.
Photomanipulations on the other hand...let's just say I spend waaaay too much time doing those and have gotten quite good at them. Lots of fun 😄 I actually took a photograph I took and manipulated it with PS and it wound up looking like half was a photo, and half was a painting. Pretty damn awesome.