Don't get deluded into thinking 450 hours means no problems. A 7 year old lightly used vessel can suffer more from sitting than being used. For starters, when was the last time ALL of the yearly required engine book maintenance was performed? Or does the flow from the exhaust elbow allow water to backflow into the engine during shutdown or stem wave intrusion while at rest (a Mainship watch item)?
As well as soliciting comments here, go to Mainship's Owner's website and ask away at issues to look for, they know and talk freely about them.