I'm writing this to provide some important to my opinion observations after some quick testing which I believe will rock everyone thinking to start moving to FSX..after a period off course

Last night I've downloaded the upgrade for v3.00 users and I decided to give it a shot so as to see what is happening.
Well...

I have exported a version of my model under developement (an F-16) using the makemdl (fs9 sdk wise) and the xtomdl (fsx sdk wise) so as to see the differences in quality as also the frame rate impact in FSX. So I'm presenting below the 2 screenshots I took for comparison. The model is untextured so in FSX is purely black..
1st observation
After Using Makemdl (fs9) the fsds V3.0 shows 3915 poly's and the ACM shows 5917 polygones - Using xtomdl (fsx) the FSDS V3.5 shows 4617 poly's... I don't know what kind of optimization is hidden behind but the result is positive.
2nd Observation
The quality of the exported model is superb. You are able now to prepare a project using 0.001 scale and the welding taking place within xtomdl after does not destroy the model small parts (i.e looking at pitot tubes, antennas etc). In fact it was the first time for me that the details of the model within fsx were absolutely the same as within FSDS 3d view! No strange shadows, jerking poly's etc
and the observaton No 3 (it's all about fps) right?
well here is the first screen shot taken after exporting using xtomdl with 30 aircraft parked in view. Look at the fps locked at 25 I got 25.

and here is the same model exported with makemdl for fs9 - fps is 6...

If that is not enough let'me add one more more important observation...What you see in these screnshots is a SINGLE LOD model

For those interested, My specs are vista ultimate on an quad core 6600 (2.4), 2 giga ram, ATI XT2900 512 mb , fsx with SP1 ofcourse running at 1600X1200 in a T965 eizo and with all sliders (on both ATI and within FSX moved to full right except autogen and any other traffic apart from planes which are set to zero.
In fact this single LOD model exported via xtomdl caused no impact at all which to me is impressive. So apart from any other problems prevent people to start moving to FSX which is not my subject, I would suggest that if you are going to produce anything for suitable for FSX make sure you use the xtomdl ...

Cheers
Chris