Our group is using a mix.
For character creation, we use ACG as it provides the best character management and the most informative character sheet with all the math done for you. The downside is that it is no longer available on the net and is not being supported/updated. It based on MS Access, so it is the easiest to edit and modify. But eventually this will no longer be the case. As someone who uses spreadsheets and access on a daily basis, I find it easiest to use. But my players like the way ERA guides you through the character generation process. We end up generating new characters in ERA, and then transcribing them into ACG or on a standard character sheet.
For combat, we prefer to use Combat Minion. Thus far, it is the easiest and most clear combat manager available (IMO). The downside for us is that it is browser based in addition to being a labor of love for one developer. This means that it lacks some of the functions that we would like, such as exhaustion point tracking, PP use penalties, creatures already statted out, and combat experience tracking. However, the developer for combat minion is active and engaged on these forums. So we maintain hope that eventually, Combat Minion will become all that we want it to be. But for now, it certainly gets the job done for the basics. We tried using the combat manager in ERA, but we couldn't quite figure it out, so we kind of gave up on it. Perhaps after a few more updates, we will try it again.
For campaign management, I'm currently toying with ERA. Right now it has an herb foraging utility that I am trying to figure out. It's more minimalistic approach to character sheet presentation is useful for NPC tracking. If it adds a usable random treasure generator and random encounter utility, I can definitely see making this my go to program. But as it is right now, it is difficult to figure a lot of things out in it, and the "guides" we get seem to be geared mostly for those that are comfortable using and editing XML utilities. This leaves me as an old fogey somewhat behind the curve. But as development and support are still active with ERA, I'm hoping that it will become more polished and user friendly. In the mean time, Wolf's Lair, the makers of Herolab are making Realmworks for campaign management. I am eying this as well, but it is still in pre-release status.