For animation: George Buza [no contest, as an avid reader of the 80s comics & then blown away by the 90s cartoon, Mr. Buza is the voice I always hear in my mind "Fascinating"] & with respects to live action in both past/present: Kelsey Grammer & Nicholas Hoult were sold in their respective roles as Dr. Henry "Hank" McCoy on screen.
1. George Buza 2. Fred Tatasciore 3. Kelsey Grammer 4. Michael Kopsa 5. Richard Doyle 6. Unknown Voice 7. Richard Portnow 8. Ron Halder 9. Mike Pollock 10. Gregg Berger 11. Chris Cox 12. Dee Bradley Baker
Future recommendations: Jeff Bennett, John DiMaggio/Swasey, Jess Harnell, Keith Silverstein/Ferguson/David/Szarabajka, Paul Eiding, David Kaye/Lodge/Sobolov, Kent/Imari Williams, Eric Bauza, J. Michael Tatum, Scott McNeil, Clancy Brown, Rick D. Wasserman, Chris Sabat/Swindle/Corey Smith, Neil Ross/Kaplan, Patrick Seitz, Jamieson Price, Peter Cullen/Jessop, JK Simmons, Liam Neeson, Richard Epcar/Armitage, James Arnold Taylor/Remar, Brian Cranston, Michael Gough/McConnohie, DC Douglas, Dwight Schultz, Jeffrey Combs, Robert Foxworth, Miguel Ferrer/Powers Boothe/Robert Forster/Kevin Conroy (if they were still alive), Kaiji Tang, Greg Chun, Steven Blum/Downes, Robin Atkin Downes, Marc Diraison/Thompson, Tony Oliver, Wally/Mick Wingert, Gideon Emery, Brian Bloom/Drummond, Mark Gibbon/Rolston, Darin de Paul, Crispin Freeman, Ike Amadi, Phil LaMarr, Kevin Michael Richardson, Bruce Greenwood, Anson Mount, Kirk Thornton, Corey Burton, Frank Welker, Daniel Riordan, & Ron Perlman
1: George Buza 2: Kelsey Grammer 3: Fred Tatasciore 4: Michael Kopsa 5: Richard Doyle 6: Richard Portnov 7: Gregg Berger 8: Ron Halder 9: Mike Pollock 10: Unknown Voice Actor 11: Kyle Herbert 12: Dee Bradley Baker 13: Chris Cox