I originally had the .95” travel servo for my trim tab and subsequently changed it to the .7” version.  Charlie Kohler pointed out that the trim tab had way too much travel with the first servo.  The travel of the trim tab is also a function of the length of the control arm but the combination that I got from Lancair, servo and control arm, gave the excessive trim tab travel.  Since it was easiest to change out the servo, that’s what I did to limit the trim tab.
 
Now, when in cruise, the trim tab indicator shows its at “3 dots” from the top (full travel).  Recently, I had the pitch trim stick in a fast descent position (2nd dot from top).  I was able to, with some extra effort, control the airplane all the way through landing with the trim tab in this position.  (The problem was a wiring issue)  I feel confident that I could control the airplane in a runaway trim condition if it went all the way to the nose down stop.  With the previous servo (.95” travel) I’m pretty sure that I wouldn’t be able to control the airplane in a runaway trim situation.

Like I said, the travel is also a function of the length of the control arm.  The ultimate measure is the angle of deflection that you get when going full up/down.  I’d be glad to take this measurement on my plane if you’re interested.

Hal Woodruff