I have owned 3 king kutters in the last 12 years for the main reason is the price, but they are all gear driven and not chain. No problems with any.
5' for the ford 850
6' for the JD 850 utility
and now another 5' for the MF20
but doing the research on them I would like to try one that spins up and not down, it's said they do a much better job.