Hi,
Our B37 2006, has the D1-30 engine, and we are very happy with its performance.
We have recently returned from a cruise up the NSW coast, where we wanted to make passage on days with not much with, and days with plenty (20+knots) of wind, and the motor performed excellently.
Always had plenty power, especially motoring into the weather, always reliable, and very economical IMO.
I have always had my local VP mechanic service the engine, and yes I could save a couple of dollars doing it myself, but the mechanic has far more experience than I do, at recognising small issues that could potentially become big issues if not address early.
If you are worried about the particular engine, get your mechanical to inspect it prior to your purchase.