I've just fitted an oil pressure gauge to give me another thing to look at rather than the road.
Cold she sits at 55, maybe up to 58PSI. Once hot she drops down between 30 to 35PSI.
Workshop manual says operating temp the pressure should be 25-55PSI.

So i'm within the limits, but its perhaps on the low side. Anythign to worry about at this stage or should i just keep an eye on it?

Don't lose sleep over it. My 300 holds a pressure of approx 25psi when warm and has run like that ever since I have had it (2003) with no problems.