I think I would do drip, much less water used and none wasted. You could put 1/4" in line valves in on the plants that would need to be shut off if they don't need to be watered as often. Larger gph drippers for those that require more water.
Using spray, it might start to run off before it starts soaking in.

I agree. Drip is the way to go.
I would irrigate the densely planted areas with pressure compensating dripline (Netafim Techline CV).
I would use Spray Stakes for the plants that are widely spaced. Use multiple Spray Stakes for plants with large root systems (Netafim Pressure Compensating Spray Stakes) .
These products are readily available online.
To prevent drainage at the lowest emitter in the case of substantial elevation difference, run each elevation on its own zone, or feed from the bottom and install inline check valves between elevation changes.

I did my slope with Netafim Techline CV, check valve, auto cleanout valves at the end of the lines and pressure regulator. The Netafim literature has a good diagram of how to place drip lines on a slope.

I would never do sprayers at the bottom of a slope pointed UP hill; this is because gravity pulls the water down to the bottom of the slope anyway; the bottom is always relatively better watered and the the top is always drier. If you must do sprayers put them at the top. However, I would just do all drip.

This was an "in progress" shot.
{{gwi:2121133}}

Looks great hoovb!
Although im not comfortable dripping where there are no plants due to water waste.
If water usage is a concern you could place a ring of dripline around each plant and connect the rings with solid poly.
Also, watering times should be short but frequent so the water doesn't migrate down the hill.

thanks for the responses! Looks like we were pointed in the wrong direction by my installer.