I have a little over a thousand hours in the P.180. It's the fastest production turboprop, and holds eight world speed records in it's class. It's quiet (inside) goes to FL410, and will outrun a Citation (but so will a duck). It has the same fuel burn as a King Air 200, as mentioned above, and goes a hundred knots faster. It has a surprisingly large cabin...you wouldn't think it's that big from the outside. External baggage, single point refueling, and for a small turboprop, it does okay on one engine. Standard avionics on the Avanti are the Universal UNS1-K and a Collins 85 five tube EFIS, and on the Avanti II the Collins ProLine.
Avantair is the biggest operator of the type, but averages at least half the fleet down for maintenance at any given time, and does a LOT of charter to get their owners where they need to be. That's not well publicised. They have a lot of parts and support availability issues, and requently make the decision to send the airplanes anyway while waiting for parts (which results in more down time and a lot of ferrying to maintenance locations). Parts are expensive, and some very difficult to get, such as brake assemblies.
The airplane flies conventionally, with no surprises. It's a single pilot airplane, but like most complex cockpits, really ought to be crewed by two.
Something Avantair found when having their various interruptions in service was that passenges for whom a turbojet or turboprop was chartered to fill in for the missing aircraft would often complain that they had paid for and expected the Piaggio...it was roomier, quieter, and more comfortable, and they liked it's advantages. One of the biggest advantages for the business aircraft department is that it looks good to stockholders and the public...the appearance of turboprop frugality with the speed and performance of a jet. Even when offered other equipment, many passengers there strongly prefer the Avanti.