thx for your answer. The limiter is really great. I played a little bit with the FGX and i must say the limiting is exact what i´m looking for. And it´s a very cool feature to work with the Transients. That can do a lot to the final mix. And the ITP Slider together with the Dynamic Perception Knob is fantastic, so what i can say after two days of testing. The only thing that i don´t know what he is doing, is the "Constant Gain Button". I know what you mean by saying "Louder seems better", but it´s a Trap. But how this exact in FGX is working and how to use i must find out. What i find out for me is, the compressor in FGX is good, but for the final mixdown i will go on using the IK Bus Compressor or Waves H-Compressor. I need Colorizing in the Mix, and for this the FGX Compressor is not the right one. But these are my personal feelings and not neutral. So, the FGX is a really really great tool. And i´m totaly happy with that, like i´m happy with the VCC from Slate.
The "constant gain" button prevents the illusion of making you think that what you are doing is better when in reality it is only louder. With this activated, the leveller effectively reduces the input to match the output - in short, it keeps your perceived volume the same. Normally limiting down by 2dB will boost the apparent (or perceived) volume by almost a third (an increase in gain of 6dB is effectively doubling the level) and the result will always appear to sound better at first simply because it is louder.
With this button active the trap is avoided as the plugin will compensate your increase in output level by reducing the input - it is the same thing as a constant gain EQ (112dB's Redline equalizer is a good example of this). I really recommend reading the manual - not only is this explained in detail, but there are some good tips to help get started with it.
FG-X is a mastering tool not a mixdown buss compressor so designed to deliberately not add "colour" in the way you mean, as that is not what mastering is about. Mastering is the process of preparing a completed, approved mix for it's intended release media and not part of the mix process - mastering tools are generally designed for transparency & accuracy, not colour.