Personally I do not like mp rotators. We have installed thousands of them, My boss likes them for some reason. And when you first put them in,they work pretty good,they do the job,they look pretty good. I just went to a job today actually,5 zones of mps. They had a booster pump for town supply and everything,although they dont have the greatest pressure regardless. I think it was about 7 mp's per zone. Out of 35 or so mp's,3 of them wouldnt open,they get stuck closed and shoot a bunch of streams straight up in the air,3 didnt turn at all,and 3 of them pissed out the left side and didnt spin. 1 year old system too.I cant speak on the competency of the installers,it was zoned well though. Take a look at hunter.com. They have videos of mp rotators working,and they are working awsome.If they worked like that all the time they would be great. But the water pressure behind those heads in the videos is out of this world,and out of 1000+ customers.very few have pressure remotely like that,most of them are town properties with big mains,artesian wells,or big goulds pumps.
If you have a yard that would be 12 zones with 8 heads a zone,well having 24 zones with half the heads is stupid like you said. But if you have a yard that would be maybe 7 zones,with 8 heads a zone,and you could do 9 zones with a couple less heads per zone,thats the way to go. If you dont have awsome pressure,you will be disapointed if you do 8 heads a zone.Im not kidding,they stop turning,they stop rotating if you turn them down,somtimes they do somtimes they dont. They have heavy streams on either side after a couple years. If i were you i would use some rainbird 3500's.We were just given a few boxes for free to try them out. They are little rotors and I personally love them,They are friggen great. The stream is nice and low so they are good for smaller areas.You can also put a bigger nozzle in it and they shoot far. Also check out a few rain bird rotary nozzles,those work great,they always spin,they throw more water than mps,but it just looks like they are doing a better job. Its all a matter of opinion really,some people might think im friggen nuts for hating on the mp's.Just my opinion though man lol, Im 100% Pro Hunter too,heads,clocks,i like their valves. If you had a pump with 60 psi they'd work great for you. I just wouldnt push the limit of heads on a zone. With 2 zones you can water based on different needs sun vs shade several other factors too.You could also just for shits, try it temporarily. Install it above ground real quick and see what 6 look like,see what 8 looks like. I will say it again im not preaching to you,if you want to put 8+ mps on a zone by all means do it.
One of the "SMARTEST" irrigation guys in the country,seriously too he teaches all the seminars,classes,courses,cic cert,everything. He hires us to do the install part while he does the valves,clock,all that stuff. He got out of it to teach irrigation,and manage properties,but hes getting back into it. He swears by mp rotators,and thats what we put in for him,on almost every job. The jobs take 2x longer because there are so many friggen heads all over the place lol. Good luck with whatever you do though