How many hours has McGann produced for audio? Shatner actually isn't the most prominent Trek actor; that honor belongs to Michael Dorn, but I'm not sure that even he surpasses McGann in total recorded time portraying the same character.
I reckon Paul's done about 130 CDs worth, between 50-75 minutes each. So that's coming close to seven season's
worth of Trek. Obviously Michael clocked up eleven seasons.
Even with Tom being a late convert to audio (but making up for it!) Up to July I think makes 48 episodes (roughly 2 TV seasons worth) so that's like 9 seasons. And there's at least three different projects on the go on top of that. So he might just equal Michael in terms of episodes; but they are half the length.