I couldn't leave the hospital without a PEG so mine was out of necessity. Since then during my surgical recovery and now facing radiation, my PEG is my friend--in fact we've named it Margaret!
I feel measurably stronger than I ever did after any of my other surgeries and these two (in one hospitalization) were by far the most invasive and radical. I feel more confident facing radiation with my nutrition not being the obstacle it could have been. I can't afford to lose weight so this is of great comfort to me that I have the means to hydrate, etc. without interfering with the site treatment and healing. I've had and am having some issues with site irritation and minor infections but dealing with those is nothing compared to the difficulties I'd face without the PEG.
I strongly agree with Brian (and others) that getting it put in before things get difficult, while your body and emotions are even more compromised, is very wise.
For what it's worth.