I've been using my Gaggia classic pro with the PID kit from shades for about 3 or 4 months and I've had my temp set to 208 because it drops down 10-20 degrees by the end of the shot.
I'm interested in seeing what other people are running and why.
I would say it might not be the temperature that you need to worry about too much in this case, but rather your PID values. By increasing your derivative, it will be more responsive to temperature changes and decrease the temperature drop during the shot.
I have mine set to 95C and it usually drops to about 91-92 during the shot.
I ran another auto configuration and then adjusted the derivative and now I'm only seeing a 5 degree drop(in freedom units) on a pretty long shot. Thank you for pointing me in the right direction.