Flip a coin.
Hi Chad, I'm going under the assumption you're talking spray heads. You're right in your conclusion that Rainbird and Hunter are a better pop up than Toro. Both the 1800 series and the Pro Spray are excellent sprinklers. You can't go wrong with either one.
I've found the Rainbird seal will start to go bad in about 10 years if they get a lot of direct sunlight. Otherwise they last much longer. I also think the Rainbird is a tad easier to work with only because of the permanent seal set in the cap. The Hunter is in two seperate pieces. That's not an issue though because you rarely have to take the cap off. You may wonder how long the seal in a Hunter will last. So do I. I don't have any customers with Pro Sprays that are 10 years old yet. So far they have minimal problems. I do know the spray pattern on the Hunter is very sharp. Meaning if it say 180 degrees, that's what you get. Rainbird isn't exact in my opinion. But, you can put the Hunter nozzel on the Rainbird body. So Chad, now that I've thoroughly confused you, flip a coin.