Yes, they offer free initial classes and even said he could go a few times before they'd need a commitment.
Maybe I could try them both a couple times each and see what he's more attracted to?
Try both and go from there. This way, you could gauge your son's interest level.
Losing interest is definitely something I'd be concerned about, especially starting at such a young age.
Yep, that is what you need to watch out for. But don't stress over it. From my experience in 30 plus years of martial arts, children sometime return to martial arts to try again when they get older into their teen years or adulthood for self-defense, exercises, etc. Martial arts won't go away.
I had taught many different martial art classes for children; I had seen kids dropped out pretty quickly. But some of them came back years later.
It's pretty expensive and quite a commitment, but I want to get him around other boys.
Yes, it is very expensive if/when a contract is involved, which is extremely common in the BJJ world. This is why I don't believe in contract.
From my experience working as a full-time karate instructor for a former popular karate school in the 1990's, my ex-instructor (
karate school owner) pushed people to sign a contract (1 year, 3 years, etc.). It led to some petty conflicts and disagreements as well as negative reviews by disgruntled students.
However, it all comes down to finding a good high quality instructor so it is worth an investment. Of course, making new like-minded friends in the martial arts world is a bonus.
Yep, good luck!