jonjie,
thanks for making us part of your decision making process.
I have had far more experience in C310R than I have had Baron than I have had Aerocommander Shrike. But I wish it was in the reverse order.
If you're talking a great workhorse with plenty of appeal for the punters, IMHO stick with the Shrike. Just take another look at that picture I posted earlier and tell yourself this is not a magnificent aeroplane!
Aside from the replaceable bungee cords on the gear, the gear is rock solid, as is the airframe. Yes, it is a hydraulic aircraft but it doesn't let go in a hurry. A durable aircraft much like your Aztec (which incidentally while not a luxury machine, is a good economic choice). I suggest you try having a chat with the guys at GAM in Essendon Airport (Australia's largest AC operator), Hinterland Aviation in Cairns or Tasair (who also have PA31) in Hobart.
In so far as Barons go, probably the best bet is the E55. Goes like a bloody cut cat, carries the load your after (contrast that with a B58 which really is a pax machine only). Economics would have to be good in terms of kg/lt/gnm (or whichever way that formula is expressed!).
It will still carry the 5 pax comfortably but STOL is not its best point given the little wheels and slippery shape.
The 310R has a nice wide cockpit, making it comfortable for punters and can take a reasonable freight load. Undercarriage seemed to take everything I dished out to it. Has very stiff legs and it is a fluke when you make a smooth landing. Big wheels help stopping quickly and they are used in STOL versions up in the Torres Straits (Skytrans).
In so far as cabin class aircraft go, a Cessna 402C IMHO craps on a PA31 whatever. Again, like the Titan and 310R it has a nice roomy cabin and is perfect for punters and freight. There was a drama with the spars having two lifes (or some such) in OZ but with a certain mod or service, the aircraft keeps on going.
As for STOL, well you can get vortex generators for them and they are simpler to operate than the PA31 and I would think last longer with a lower boost level. They have been operated successfully in PNG too.
These are all pilot perspectives. Perhaps the same question posted on an engineering section of Pprune may get another response.
Cheers,
TJ
