I knew I recognized this song from somewhere! Hell or High Water was such an awesome movie.

"Less'n" is slang for "unless", and he's saying he's gonna keep going, unless he starts listening to his common sense and turns off of his wild path :)

I don't think so because if you listen closely it's a hard "s" at the end

YEP

Sad that i ain't from the US.

Well hell, probably outta move then

Hell, this is better than 90% of the country "music" they're playing on the radio these days.

No. Nickajack.