We started Soccer Tots w/ our young 2 year old and dropped after 2 weeks b/c it was more work for me. At that age it's parent-assisted and some get it and do well and others, my son, didn't want to participate in the activity. He wanted to throw the ball in the air, kick it in the opposite direction asked, and not cooperate. We were grateful they refunded our money.
However you said your son is advances for his age, then it should be a good fit. The Soccer Tots program is great and we loved the coach (an SMU grad student). Our older son (3 yo) did stay in and loved it. (We went to the one at Sole Roll near the Galleria.)
I hope that helps!
A.