My son has played for the Tri State Arsenal for the past couple of years. It's a 100 mIle each way trip for us, so that might explain how much he and I think of the organization. He has played for their #1 team each year, but don't underestimate the other teams at each age bracket. Some of the older #2 teams also have D1 prospects on their roster.
My suggestion, when it involves picking a HS, is to pick the best academic one your son can get into. If we picked solely because of baseball, he would be in a far lesser school. The work he does on his own and with the travel team makes up for what the HS does not do. And they are lacking quite a bit.