My friend Serge and I both bought our Bobcats at the same time, I installed rudder servos, he did not.
The only time I used rudders were on landing,...to help line up the runway. Winds are usually straight down the runway at our field, so I found I didn't really need the rudders, so I removed the servos, and fixed the rudders. I also have the elevator servo inside the stab now, so plane is alot cleaner (and faster) without all those servos hanging out there. I would say, if your field is not prone to strong cross winds,..then don't bother with putting rudder servos on.