I sometimes reference Champions/Hero System (5e hard copy or Champions Complete PDF--6e, I believe) when researching effects for my own system, but I've never played the game and I don't have an interest on new manuals for most of the reasons mentioned by many here (and fact that the books I already own cover my purposes for the game). I find the system to be more complicated than it needs to be for what it tries to do and I don't really like the core system (stats, task resolution, phased combat rules, etc), beyond the effects component.
I also find the manuals wordy and hard to follow (though, I've adapted over the years), with excessive use of hard to remember acronyms for stats and abilities that use multi-word phrases like "Offensive+Combat+Value" (OCV) or "Defensive+Combat+Value" (DCV) when single words will do (Combat or Defense). Now I have to remember literally dozens of acronyms, like I'm on the freaking military cuz the game designers can't come up with ability names that are less than 3+ words long, yet can't be bothered to write those names in full for 90% of the manual, even when dealing with obscure Power Modifiers, "adders" or whatever they're called.
If I wanted to play an existing effect-based system I would just go with Mutants & Masterminds (which is already close to my ideal, except for some stuff I would've done differently or don't like about d20 System's 3e) or a modified version of the old Marvel Super Heroes (FASERIP) RPG to allow for random damage.