There are separate EQs for the clean channel and the high gain sides. Its like a 6505+ but better in that regard. Ch 1 has a 3 band EQ with pre gain and post gain controls, and Ch 2 & 3 share a 3 band EQ but they differ from the 6505+ in that on the Invective Ch 2 and Ch 3 each have their own pre gain and post gain controls. I dont mind this, as most of the issues Ive ever had with global EQs is when I want to go from clean to dirt. After you are out of Ch 1, the EQ for the medium n high gain channels is not like to need to be so drastically different that you cant find a happy medium that doesnt feel like too much of a compromise, if any, from one to the next. My Marshall DSL is a killer amp, but that's the main issue I have with any Marshall (save the JVM), is the fact that the EQs are always global. With the pre gain and post gain controls on both channels, it makes finding a unity setting that much easier as well, because you can set them up to where there is no noticable volume jump from one channel to the other.
Far as the Master Boost feature, there is something to that as well, but for me it hasn't been nearly as drastic. I spoke with one of the guys who helped engineer the Invective about this, and basically what Ive found is that the difference is involved in the Master Boost being induced into the circuit in general. Adjusting the level will increase (or decrease) dBs, but its the boost being engaged (and therefore added to the signal/circuit) that causes the change in the tonal charachteristics of the amp. There are still usable tones to be had without utilizing the Master Boost, especially on Ch 1, but engaging the boost is what removes the torniquet from the testicles of the amp and allows you to go completely balls to the wall. Engaging the Master Boost is where the brootz kick into high gear for sure. This SOB can chug with the best of em and even puts many others to shame.