Painting brand new fibreous plaster?

Hi all, hope you can help me with some wisdom. I have got to the point in our reno that we are ready to put some paint on the new walls and ceilings. Only thing is we used ornate fibreous ceiling panels on the bedroom and ornate fibreous plaster cornices from Baileys every where.

The guy at one paint shop said to only use an oil based primer sealer and another said to use an oil enriched acrylic which sounds good being water based. Both said to do all the raw plaster and gyprock.

Are they just trying to flog me more paint or is there some good advice there, if so what is the general feeling, oil or water based primer sealer and does raw gyprock need primer sealer or just the joints?

Thanks in advance.


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