I'd think about dynamic EQ more like multiband compression but just with the ability to change the Q of the band effected, mixed with an EQ, as opposed to just another type of EQ. This might help you get your head around it better.

As far as I know, there's not much diference betwen a standard grafic EQ and a parametric one (that just has a ton of active bands) other than the controls and the visual interface. The lack of a Q control is the biggest, but boosting and cutting will just be like with a parametric EQ, but with a fixed Q at each freqency. You just generally get more control and visual feedback with a parametric EQ, but that's not saying you need that extra control every time, nor that feedback, providing you can hear what you are doing and like it. However, there are some issues that you just need a parametric EQ for, as a grafic one will not have the flexability to be able to fully solve them. For instance sweeping the spectrum to identify exactly where a problem freqency lays, you can't really do with a grafic EQ without messing up any bands you've already set, as well as the obvious one of not being able to adjust Q and being stuck with the same shape bell curve for every band.

If it sounds good, it generally is good. However there are some reasons you might want to use a specific type of EQ to solve specific things. Too many to go fully into here, but for example linear phase is great for parallel tracks as unlike a standard EQ, it doesn't change the phase relationship between them (but can introduce pre-ringing especially in low end material). Most things in audio have both pros and cons, and you need to weigh them up in each situation to help you land on the right tool, depending on what you are trying to acheive with each particular move you make, and what pitfalls of using a certain tool there may be.

I always go by the mantra know why you are doing or using something, and if you don't, ask yourself do you even need it? Which seems to be what you are doing here. :) A normal EQ is perfectly fine to use for general tone shaping in most cases, unless you have a specific reason to use something else (like a perfectly valid reason you might want to use a dynamic EQ on vocals is if the problem freqency isn't present all the time, and you don't want to be cutting there when it isn't present, but if you just need less 300hz overall, there is really no reason to not use a normal EQ to do it in most cases, that is unless you are specifically aware of a reason why it wouldn't be the best tool for that specific job in that specific situation, due to other factors about the track or it's processing that makes it make more sense to use something else instead). ;)