I've had an Aerostar 702P for about two years. Generally, I agree with Tim. Bottom line: it's probably the best bang for the buck in terms of performance, but that doesn't mean it's cheap (cost, like energy, rises exponentially with speed). I'm also not sure it fits your mission (more on that below).
How much you spend at acquisition is hugely important. You can buy a cheap Aerostar with run-out engines, a leaky cabin, and 1980s avionics that's a bloody mess, or you can go spend $400k and have a bird that flies as well or better than a brand-new production airplane. I took the latter route and have been pretty happy. The plane hadn't flown much in the year preceding my purchase, so my first annual was about $25k. I fixed everything that even looked liked it wanted to break. I didn't need to spend that much, but I like to run a tight ship. Most owners say their typical annuals are around $15k, with a big one every so often when something expensive needs fixing. The U2A engines are some of the most reliable big piston engines out there.
IMO, old-and-well-maintained isn't much different from new; I flew plenty of brand new Cirruses that had teething troubles, and the Diamond guys never seem to get their TwinStars out of the hangar. Obviously, it's less bitter when warranty is covering those bills, but you're paying for that warranty in depreciation.
Here's one way to think about it: you're acquiring an aircraft that, new, would be around $2mm (a new Baron is $1.4, and it's neither pressurized nor turbocharged). You can scoop up the airframes for well under 1/4 of that price, but your operating and maintenance costs will be that of a $2mm aircraft. The great thing about the Aerostar is that it's far and away the most efficient piston twin out there. It flies faster than anything that's not a turboprop (and faster than some King Airs), but it does that by being remarkably efficient. You can true out at 240ktas burning 44gph or pull back to 205 and burn 30gph. Consider that an SR22T (with, ahem,
one engine) runs about that same speed on roughly 19gph! Not to mention that you need to be up in the flight levels freezing your ass off and wearing a full-face mask to get even close to 200 true. (I'm not bashing Cirrus at all; I flew one for years and think they're exceptional airplanes. I'm just making the point that the A* is wonderfully efficient if you want it to be. Reality, of course, means that most of us are lead foots.)
I've found AAC's numbers here to be about right in terms of cost:
http://aerostaraircraft.com/Super 700 Operating.pdf
The guys at AAC are top-notch; the only thing they don't do is make new planes. The Aerostar is one of the best supported aircraft out there, and parts are more available than for some in-production planes. The owner community is fantastic. Aerostars are quirky, though, and all that efficiency means stuff is crammed together in the damnedest ways. It's not always easy to find a mechanic familiar with the bird.
Now, all that said (here comes the buzzkill) I'm thinking that a big pressurized twin might be overkill for a 150NM trip. At that kind of distance, speeds don't matter all that much, and climbing up into the flight levels is just a waste of fuel. I wouldn't bother climbing much above 10k for a 40 minute trip, so who really cares about pressurization?
That said,
doing this and
seeing this are just stupid fun.
If after all this you're seriously considering the A*, please feel free to PM me.