I'm late to this long-running thread. I got my architect's license at age 28, the youngest in my graduating class to do so (as far as I know).
My first reaction was relief that it was "over", and my second reaction was mild fear. I was aware that I really didn't know that much about architecture, and yet I was just given permission to design and stamp just about every kind of project except bridges and hospitals, etc. Who else out there had designed the buildings that I already lived, worked and shopped in, without really knowing what they were doing?
That's when I realized a stamp didn't really mean anything except that you knew how to go to school and take tests. What really counts is your personal sense of professional responsibility: giving it your best, not being afraid to ask questions, knowing when to bring in other experts to help with your limitations, constantly applying "lessons learned" (hopefully from other people's mistakes!), etc., eventually building up to years of technical experience and (hopefully) wisdom that adds value for my clients and safety for the public.
I once read that the average age of the engineers on the Hoover Dam project was 28. As the dam filled, they started getting minor earthquakes in the area, and they eventually realized it was from the weight of the water bending the earth's crust! Imagine the sense of personal responsibility if that had ultimately gone wrong - - destruction of the southwest on a scale so much larger than Mulholland's San Fransiquio dam collapse.
So you have to take your profession seriously, especially as it relates to life safety. I have no problem with plan checkers or other peer reviewers looking over my work, as long as (a) they do it in a timely manner, and (b) they generally know what they are talking about, and (c) they actually review the plans, as opposed to just spitting out boilerplate plan check responses.