Richard Hunt: What can be said about an original Muppeteer? They created the performance that would go on to be replicated and imitated and eventually massaged into characters that have become so iconic. As the first to perform Scooter, the character hadn't really come into his own yet, having more of a meek and mild temperment, combined with an almost "subservient underling" attitude. Richard's later portrayls fix this, however.
Greg Berg: Greg is servicable as a younger version of Scooter.
Adam Hunt: It's unfortunate that Adam has such limited material, as I feel like his voice shows promise.
Matt Vogel: Not one of Matt's better replacement performances, sadly. It's sufficient for such a minor role in the video game, but I don't feel like it would've worked in a larger role.
Brian Henson: The performance itself isn't bad, but the voice is a little... 'whiny', for the lack of a better adjective.
Rickey Boyd: Although Rickey doesn't sound identical to Richard, I actually feel like he's one of the stronger replacement voices.
David Rudman: David appears to be the official and steady performer for Scooter, which allows him to have more opportunities to play him. David's managed to finesse his Scooter and establish his own tone, and honestly, I feel it's more polished than Richard's. David's voice is the one I hear when I think of Scooter, and as weird as it sounds, his voice, persona and attitude all jive well with the portrayal of a stage manager/assistant director. Just a very relaxed, matter-of-fact, get-business-done kind of attitude.
David's getting my vote on this one.
*This voice compare brought to you thanks to the efforts of Ghosty404