If its the only school in your area and the other school will be limiting intake to their own area, it doesnt sound like you have much of a choice but to send him to that school.

But i wouldnt be concerned with the low income status of the demographics because even the best schools with the wealthiest parents still have ratbag children in them lol. You've got 2 years to check the school out and perhaps try and get to know the teachers and some other parents there. You could ask some of the current parents what they think of the school and try to get a feel for it. And also keep in mind that the children that are there now may not be there in 2 years time....or they would have grown up a little.

Its hard when your options are limited in this way.