In general, charters are public schools that can operate without many of the constraints followed by the public. This means they can vary from awesome (when you have folks who know what they are doing and are committed to education) to horrible (for-profits with under-trained and under-paid teachers, alternative cutesy "theories" with no supporting data, etc.). But as with everything else, most of them are average -- maybe a little better here, a little worse there, but largely the same bell-curve distribution as the publics. You would need to research very, very carefully to figure out where your particular options fall on the spectrum.
I am a fan of starting with the local public school and then changing if that doesn't work.* We did not do this with our daughter, and it was a mistake. We had good reason (very ADHD, so we assumed a local Montessori would be better), but we were wrong. We ended up putting her in the local public school in 2nd grade, and they were much better equipped to manage her; they had several ADHD kids every year, so it was basically par for the course for them. But because we waited so long, it took DD several years to really fit in with the other girls in the neighborhood, all of whom had been together since K -- and she is a highly-social kid, so that hit her hard.
OTOH, we put DS in the public school from the get-go, and it has been smooth sailing on all fronts (although admittedly he's a lot easier, so it's not exactly a fair comparison). This year we had to send him to the less-desirable MS one town over because of stupid school zoning rules. Everyone here looks down on that school, as far as I can tell because the town is poorer than where we live. And I will admit, I have not been overwhelmingly impressed with some things (there is one particularly stupid teacher, and fewer "extras" than the closer/wealthier MS). But he is happy as a clam, has made a bunch of new friends, has some really great teachers, and continues to do well in hard classes. Which is pretty much what matters in the end.
Tl;dr: Do your research, visit the schools, talk to the principals and teachers. Just don't overlook the value of having a pack of friends your kid can walk/bike to play with.
*I would make an exception if there was a specific alternative school that offered something your local school didn't, like a language immersion program you wanted your kid to be involved in.