I'm happy to stick the Woodleigh projectiles and wary of using monos, 1.) because they are not needed where I hunt, ie a lead free ban and 2.) if Woodleighs have worked in the past without problems why risk a hundred year old rifle for no purpose.

Lead free bans are the only reason I would consider using a mono bullet in an old rifle.

Secondly, the Woodleigh bullet in the picture above is a FMJ. I believe they recommend to use FMJ's sparingly as well, as the jacket can be quite solid as well.

I prefer to use the SPs instead and FMJ's only during load development and during actual hunts where an FMJ is required.

I would use monometal, banded bullets in stout barrelled bolt action rifles however, if I felt the need.