now that i finally have a engine service and programming track i spent a few hours fixing and programming engines. some had decoders installed, others had decoders replaced. don't know exactly but i guess around 50 or 60 more engines are now ready for service. i usually don't spend too much time on exact speedmatching as this will change over time anyways. according to my experience differences in speed of -/+ 5% are no real issue anyways.
one thing i noticed while installing decoders. kato sd70ace and digitrax dn163k1c do work. however, the front end of the decoder will be bent to a degree i don't really like. electronic boards should not be bent. at least that's my opinion. also due to the construction of the drive you might need to either shim the decoder or press the contact tabs of the drive downwards. otherwise there might be contact and seating issues. other than that the kato sd70ace are extremely smooth runners.
today i had two cleaning trains running. i use tomix track cleaning cars for this purpose. some have decoders installed in order to control rpm of the motor or even shut them completely down. using the sanding or polishing disks will cause the trucks to collect dust. after a while electrical contact will fail or the pickups will even short out. these cars work good but are prone to failures. the pickup design features tiny springs which may melt or bend due to too much current. from my experience i'd say these cleaning cars will hold 20-30 hours maximum before they fail. this should give plenty of runtime and cleaning on normal layouts. having a 60m/180ft lap distance will of course result in a lot of run time on these cleaning cars. today two of the 6 i currently use failed for the finaly time. will probably use the for parts. leaving 4 for service. since i know they don't hold up for ages i always have some spare ones. currently there are 6 brand new and unrun ones in stock :-)