I am finding that using aero alone is running the risk of sprinklers clogging...It happened to me and caused hermies, but If I had had a closer eye at the time, I might've avoided a problem...As Z says. You cannot see the sprinkler not working! I think if you want to run both drip and sprinklers, it cannot hurt you a bit...I would however watch my rez temps...especially if this idea has you using 2 pumps. As far as 1/2" pvc...people have been using it for years...I like using the 3/4" in with 1/2" irrigation tubing. I haven't tried any 1/2"

Can't wait to see your system