It's very reliable, but somewhat manpower intensive...at least in my experience. If you have your router sled set up properly it'll work very good. You may have to do some sanding afterwards, but for me it'll do until I get the $$ for a proper thickness planer.
Here's a shot of my router sled set up and the resulting thickness planned body.
Originally Posted by Chewie219
I have seen many threads of people using a router to plane down a body. How reliable is this? I have a piece of Douglas fir that is at 2" right now. Should I even drop it to 1 3/4"? Thanks for the help.