I think this is actually a somewhat tough comparison especially after seeing Anthony George in his regular role on, "The Untouchables" playing G-man Cam Allison, (he could be a pretty bad dude at times). Unfortunately Dan Curtis or any of the directors did not focus on this part of Anthony's capability as an actor when he took over Burke Devlin. He really played the part sweet as he was probably directed to do, (so people would be sympathetic towards his affection for Vicki). Isnt it interesting how most of the heavy male characters in DS eventually go soft, (ie Roger, Willie, Barnabas, Quentin and the list goes on and on). When Anthony took over it appears that it was Burke's turn to mellow out.
On the other hand it would have been interesting to see Mitchell Ryan playing say, Jeremiah's ghost. As we all know Mitch never got the chance to play any supernatural characters so one cannot comment on how effective he may have played that type of role. It would have also been intersting seeing Mitch playing Jeremiah before Angelique began reeking havoc. I find it hard to visualize Mitch playing a character that was friendly with Barnabas.
It appears that the switch was made at a precision time in the storyline, (with a little help from the writers no doubt).
Thats my two dollars worth.
B