18 years from purchase I can say that the dome is mainly maintenance free. Just clean it as you would do for a car.

I never had any leak of rain or even snow.

What I appreciate most is its thermal stability. Dome closed, the internal temperature follows the external temperature with no more than 1°C difference. So I can open the slit and instantly use the scope because it is already at ambient temperature.

If I would change it in the future, it would certainly be due to the evolution of the observatory instrumentation and the need for a bigger size dome.