THIS. When I started out making my webcomic, I did feel kinda guilty about tracing because I want to hone my skills and be able to draw ALL THE THINGS...but when you are pressed with a deadline to get your page done, sometimes that "self pride" is a liability.
I'll use 3-D models to help me with things like rooms and perspective; if I find pic of a car/object with a good shot/angle I'll trace over it...you're NOT going to know how to draw everything perfectly- and dont think of it as cheating, coz a lot of the pros who do mainstream books are doing some of the same so that they can get a monthly book done and get paid.
A lot of small press artists who do cons and other freelance gigs- they are trying to make being an artist their career; that means getting work done so they can make a living off of it. In this type of work you've got no time for guilt.