Never being 100% satisfied with your work is all part of the game - were it not for this there would never be the push to continually improve. There is always some part of the finished product where you didnt do your best work - slight "off" day etc. This will glare out at you like the dogs balls, but Joe Blow would never notice it.
I quite often walk away from a restore just before the end - i find i get too finicky and need to look at it with fresh eyes again.. i often come back and think "christ - i did nice work there"  whereas a month before it was irritating the crap out of me and i was ready to throw it out of the window.
But putting it all back together and seeing all that hard work come to life as a beautiful looking shiny pin is just the very best feeling - it will take pride of place in the line up for quite some time!