Your voice sounds excellent, really fitting the part of a gritty, whiskey drinkin' warrior, or at least, that's the character I envision. A great persona for a Fallout narrator in any case.
For criticism, there are minor details I would like to put forth:
• The audio quality sounds half-way between a studio microphone and a Skype chat (I'm guessing that's because you used a radioactive potato? haha) - use a higher quality microphone if you are able
• Only a couple or few times can I hear what sounds like your tongue smacking from the inside of your mouth - if you can, try keeping your mouth a bit drier to alleviate the sound, as the presence of saliva can make the smacking louder and more common
• Only once I think did I hear a word end on a breath, but to me it sounded unfitting; I would think breath or breathing in voice acting is used better only to convey emotions and/or a character doing or having done some action
• There are a few instance where you seem to short-cut the pronunciation of words, e.g. "forgotten" became "forgah-un" - try pronouncing them fully each time, or if that feels to cumbersome at times, merge them into other words so they roll better of the tongue
Having done in a single take as well, much kudos.
Hope I've been constructive for you :)