after trying and using just about every eq available.... at this time my most used mixing eq is the one included in sonar X3 that's part of their pro-channel, sounds great in all 4 modes (hybrid, pure, E and G ), and has a great, useful, zoom view . For mastering duties i use DMG Equality and both solve everything most of the times (except for some pultec or api emus i like on certain things...)
i have used the sonar eq on simple mastering jobs and it works just fine (except when you need more than 4 bands and 2 cuts)