I am satisfied with the results of cutting my own hair, but i'm not one who strives for an evenness i don't even get to see...
My usual payment for getting my hair cut is they (the friend/barber) get to choose the hair style, and i'll wear it for a week or more until i weary of it, and clip it short.
True story. On one such occasion, a friend gave me a tonsure. I liked it so much that i shaved around it, and held it for more than a month (the last few weeks letting the hair grow out, so i could clip it down to what constitutes evenness for me) And during that month, i got pulled over and had my car searched, a story sufficiently interesting on its own i often forget to mention i had a tonsure at the time. True story.