30mb or 37mb regulator?

Spriddler

My m/h has a 37mb regulator but my son's caravan has a 30mb unit. There seem to be more installation options for 30mb installations: refillable bottles, changeover valves etc.

Can I just change to a 30mb instead of my current 37mb regulator? I'm thinking that the cooker, water heater etc would not be compatible.

I realise this 'should' be in Technical Tips but that section is divided into either 'Caravans' or 'Motorhomes' and this is relevant to both