I have a float RL, I dont believe it had been serviced in the year i’d owned it before i did a service.
I changed the oil, changed the seals and dust wipers. The oil was pretty dirty TBH and the wipers were dirty. I never noticed any difference after the service though, they were marginally smoother but it wasnt huge.
I guess keeping the oil clean will make them last longer though, the stanctions wont wear out as fast??
Depends how much its been ridden, I only did mine because they blew a seal and they only get ridden properly maybe once twice a month 🙁