I've done LPs of KQ 1-3 (as well as SQ1), and they're not the greatest, mostly because I did them at random and thus I act kind of randomly, especially KQ3, where I had a friend guest star and we had more fun with each other than interest in playing the game. I don't try to "act" to much in my LPs and let my words just come out, which unfortunately include a bit of profanity (which is not added for comedic effect eg AVGN style, I really am a naughty girl and swear way more often than I should in real life. I'm working on it).
And I SUCK at voice acting seriously bad.
I prefer commentary in LPs (which I find sort of necessary, since it differentiates a "Let's Play" from a "Let's Watch". You can only do so much so many times in a game before it becomes just like everyone else's playthough, and commentary is what makes each one unique.