You're referring to the new "MP Rotator" nozzles made by "Walla Walla Sprinkler Company", which is a subsidiary of one of the big guys - Hunter, I think.
Anyway, yah. We use those all the time. Just installed another system last week using those. They're great, IMO.
Watering times are approximately double or maybe a little more. But why does that matter? They're cool as heck to look at too. Every client who we've installed them for just loves the way they look.
One of the best benefits to the MP Rotators is they have a nearly perfectly even precipitation rate when spaced properly.
They are designed for low-flow, low-pressure conditions. They work great when you want to put, say 12 heads on a zone but there wouldn't be enough flow to use 12 regular Rainbird 1800 heads and nozzles. It helps you fit just a few more heads into one zone and saves you from creating an additional zone.
One last thing - the MP Rotators aren't actually sprinkler "heads". They are just nozzles. They fit on Rainbird 1800 series heads (instead of the RB nozzle) and I believe Toro pop-up heads too.
We've had great success with them. Been installing them for 1.5 years now. Reliable so far too. Haven't seen one go out yet.
I use them in repairs where the homeowner has installed it and gone too far on the head spacing or placed too many heads on a line. They are great for that application. You just move a few heads a bit and change all the nozzles on the zone to the MP rotators and it overcomes the design problem.