Not sure if this is a silly question, but here it goes:

Is there any dissadantage to a steam boiler in a dual boiler system being smaller, but run at a higher pressure?

I was thinking that it might be possible to have a very small footprint steam boiler running at say 9 bar, which would leave you with around 4 times the trapped steam per volume that a standard 1.3bar boiler. Assuming this is good, then the boiler could be 1/4 the size right?

The only thing that I can think of is that the recovery time would be substantially longer, and the water would be up at 180c

Maybe scale problems as the same amount of water would travel through a smaller space?