That may be a nice bus. The 5.9 is the same as my engine, but mine is in a 26' FE. If you're a weekend tripper and don't travel in your bus much you should find that bus ok generally speaking. If you're going to travel on the interstate you will likely want a bigger engine if you have that choice. That bus sounds ok, but most of us would prefer something with more power.
Also consider the transmission number and the rear end ratio if possible. You can find a calculator here that will show you what speeds a bus is capable of with the current gearing.
Take some time and read more threads, considering your intended use of your bus.
For myself I'd pass on that bus because of the size of the engine. I have the same engine and it feels quite sluggish in this medium size bus. I wouldn't choose the same engine for a longer bus.