Many years ago, I fitted an ESU Lokpilot to a Lima class 117 DMU:https://www.youtube.com/watch?v=89UzmOeuCk4
It totally transformed the drivability of the model.
My suggestion would be that if you want to fit decoders to Lima locos, be selective about your decoder choice: a good quality decoder can transform the loco, a cheap decoder will not.
As others have suggested, Lima models always benefit from extra pickups.
The pickup issue on Lima locos is widely misunderstood. Irregularities in the traction tyre thickness, together with vibration from the motor caused them to constantly wobble which in turn caused loss of pickup.
As you can see in my video, the 'growling' (and therefore, vibration) of the motor has been significantly reduced by the ESU decoder properly controlling the motor. Net result was that it ran significantly better. I didn't realise that a Lima loco could actually run so well!