Hi Mick,
As a general rule all new Farish N scale and Branchline 009 locos will be fitted with coreless motors.
Some of the older Farish locos as they are being upgraded to NEXT18 decoders and sound capability will also be modified to include coreless motors, but possibly not all of them.
Branchline OO locos will predominantly be 3 pole cored motors but this is very much dependant on size of the loco and the required pulling power.
Dapol do not use coreless motors in ANY of their models.
Information supplied in good faith.
Wiggy.