JR has the MP line of brushless servos but the only one I found on Horizon's website was the tail rotor servo @48 in/oz of torque hardly suitable for control surfaces on a jet. I think we will see more of them in the future but not real common yet. I have installed and serviced hundreds of industrial servo motors, albeit larger motors, but constantly moving on CNC equipment and industrial applications that run for hours on end with. Dry little if any maintenance required. I have seen very little "brush" issues. I think the current crop of premium coreless digital servos are very good and have been giving a lot of us very good service. Initial servo setup, with proper linkages, including proper mechanical setup is probably the most important factor affecting servo life. As a model ages if you start noticing gear slop, servos not centering, erratic movements, or physical damage then you change them. Otherwise no need to just replace them. YMMV....

DR