Has anyone mounted this show?   WHat are the pros and cons?  Anymore suggestions for murder mystery?

Being a "techie," I have fond memories of this show, too.  We did it in a very small, intimate theatre (72 seats!), and getting the statuettes to "disappear" in front of such a close audience became a challenge.  Instead of having an actor grab one in a blackout, or having a panel behind the mantle slide open so a stage hand could grab one, I built a mantle with eight little trap doors remotely operated via padded solenoids (remember, two statuettes remain on the mantle to the end) and a padded cell below each door, inside the mantle for each statuette to fall into.  The audience could not see the top of the mantle so the trap doors worked perfectly.  They were absolutely silent and it became a fun thing for the audiences, as well.  Using misdirection or when something was happening on the other side of the stage, in full stage illumination, I would release a trap door and drop a statuette into the cell below, out of sight (one at a time, from alternating ends until only the two at the end were standing in the center of the mantle).  The audiences would, en masse, witness a murder and immediately turn their heads back to the mantle to see another statuette had already disappeared.  One couple came back the next night and while he watched the play, she stared at the mantle to see how they disappeared.  She finally saw it happen and immediately whispered her discovery to her partner.  This show was so much fun for me because of the audiences amazed, and varied responses to those magically disappearing statuettes.  It didn't hurt that the acting was top notch as well.

Great show, and the relatively cheap royalties don't hurt.  It's cozy and creepy at the same time.  Excellent and fun characters.  I frankly don't see anything wrong with a happy ending for the finale.  After all, it's not like Agatha cheats us in the area of killing!  Also, it's a great puzzle.  When my high school put it on the kids really got into the script and found at least 20 dead-on clues for the murderer which Agatha gave throughout the show.  But there are so many red herrings, very few audience members ever figure it out. 

Yes, I used a female as Dr. Armstrong. She was a great actress and it helped balance out the cast of men.

I've also seen females used for Marston, Wargrave, Blore. It is trickier for Marston without adjusting the slant of the lines, if memory serves. I believe the character flirts with Vera, and they had her flirt with Lombard instead.