You folks should not forget the fact that each flight or stage of a flight, can make completely different demands on your system, especially when using 3rd party addons. For instance, I tend to use different configurations files depending on what I am using, where & what I am flying (heavy airports usage, takeoff/landing phase, cruising high altitude, VFR etc). So if you stick with one particular config, it might be smooth on a single flight or part of that flight, but load up another flight/area or get to a different stage of that same flight, and stutters/problems may creep into your flying. Nearly all cfg tweaks can be put into a separate cfg file and loaded up via the graphic options even during a flight. For example, take the Texture_Max_Load variable which defaults at 1024, you can either run REX or another similar program before loading up FSX to force it to stay at 4096, or you can manually change it in FSX.CFG but as soon as you edit the graphic options within FSX it will return to default (unless you running REX or something to prevent that which takes up some resources). Now instead of changing the FSX.CFG variables, which btw only get read at FSX startup and not during any time while FSX is running so it is overwritten by many defaults as soon as you edit the graphic options during any stage while running FSX, try creating a separate cfg file. This can be done by simply using the save option within the FSX graphic menu, give the file a particular name, find it on your PC (somewhere within my documents) and use that particular file to add things like TML=4096. So once you are flying you can load those cfg files during any stage of a flight and it will use the variable stated within. Using this method, for instance, you could have 1 cfg files with TML at 1024 during a busy airport part and load another cfg file shortly after take off with TML at 4096 (this is just an example). Using this method you can also easily edit things like autogen etc within the file to make your particular flight over a particular area as smooth as possible. I tend to end up giving my cfg files names like Busy airports, Flying over NL2000v4, High alt cruising, Using complex Aircrafts etc, all you need to do is find out what are the best settings for your system for a specific aircraft & flight and save those settings to a specific cfg.
Hope that makes sense.
Lukext: I personally would recommend CS 757 but mainly because of the excellent UHDT world liveries that are available for it via McPhat. So far they have done 3 world airline releases, 5 liveries each, in UHDT paints all excellent quality plus they are about to release a 4th one soon. Once you go HD or UHDT, believe me, everything else just looks 'Dull'.
Devrij: Don't forget that scenery addons (not all of them) can be stored on a different drive if need be when you install it. For instance, pretty sure NL2000v4 can be installed to a different drive then FSX. This should free up much space on the FSX drive, you may even want to try moving scenery manually if you get desperate on space. Simply find where the folder with scenery & textures is stored, copy (move it once you tested it) it to another drive, edit or change the scenery library file to make sure it points to the correct area and Bob's your uncle. btw, at CS is selling the 707 at a $20 discount, might be worth it to you now?
Will be transfering FSX over to it tonite. Should leave about 30GB free on my c300. Will install Rex on to the C300 leaving a good 40GB of the vertex for addons 
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