I just received a Dash 8-40C replacement for an older model under the $20 warantee deal. Neither one of the Rapido couplers work. They will not engage any of my Rapido cars or other locomotives. My first $20 replacement didn't run either. This is my 2nd $20 replacement where the coupler didn't work. BooHoo! I give up. Somebody has to check up on quality / design.