I think it's good to have the experience of being one of the oldest kids in a classroom. The older kids are usually the ones who lead, and everyone needs practice leading. Also, the older kids can help the younger kids. 3 years of the same thing is just too much.
In your situation, I would probably keep him in the daycare (though you didn't mention a difference in costs that might sway the decision). The question would be what happens when he does go to kindergarten, and takes a step back academically from what the daycare teacher had him doing.
That's when other considerations come into play, regarding a possible grade skip or in class differentiation. Is Mathew tall for his age? How's his motor control? Is he mature? Where does his birthday fall relative to the age cut-off? What can the school offer? etc. You'll need to gather a lot of information and consider a lot of variables.
When the time comes, the Iowa acceleration scale may prove handy. I haven't used it myself... my oldest is 4.
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