I have both the Silver and the Rare Black Version. I disassembled mine, cleaned all the gears and shafts. I used Red N Tacky 2 for grease and oiled everything up with Labelle 107 and both of mine run extremely smooth and fast, but when it comes to pulling, it can only pull 6 out of the 10 Pullmans Lionel Made for it :-)
I know a few members on here, had a DC can motors installed, and was able to keep the original railsounds. I still might go that route, but wiring to the DC can motor board has me a little confused on how it was done.
Timko Repair Depot does the motor conversions, if your concerned about the pulling