C7,
A quick look at your specs (6 pax/high DA/baggage space/speed) would point pretty well at the 109S. It's got much more cabin space than earlier 109 models, even more than the 109E, and has gobs of power from the PW207's. The baggage space in the boot is extended way back over the earlier A/AII/C, it will cruise close to Vne when light, and has a good range with the aux tank fitted. Next year's models will also have HUD available, and the standard EFIS is really first class. Air con actually works, and I suspect that will be a necessity where you are.
The 407 and the Koala are good, but won't be as good. 6 pax won't have as much room as the Grand, nor will the cruise speed be up to the 109S. The 130 and 135 are nice but unlikely to have the payload/range, and there is always the issue of support: maybe do a search on Rotorheads for previous queries which will give you more information? There are quite a few threads extant, you'll see links to a couple at the bottom of this thread page to help you
When are you in Ft Worth? I'll be there in 10 days time, for a couple of weeks
