I don't find 7% to be much of an improvement over the cost and work needed to hang Orca. You can get paint with the same reflective value as Orca too!
Much cheaper!
Regular flat white
ceiling paint is 87% reflective. And that is diffuse reflection (spread out) Ceiling paint contains actual reflective materials - fine ground - to increase reflection, over wall paints.
Orca is diffuse and 94% reflective.
Behr 4650 Ultra Pure White latex paint is 94% reflective (diffuse)
the bold type is an embedded link
The only two things higher are:
Mylar
Radiant Guard (house wrap or attic wrap)
https://www.cycloptics.com/sites/default/files/RadiantGuard.pdf
These 2 are 96% reflective. These are also specular (or something) reflective. That means that the light reflects off at straight angles from where it hits.
This can be a minus in a way. You may inadvertently create a light "hot" spot and burn a part of your plant...
I use some mylar on portable coat racks - Kinda like a reflecting wall for between lights - one working, and one not. Helps keep the light back on the plant.
I have not ever "burnt" a plant with it's use. However, it is only secured to the top bar and floats in the breeze. You can "see" intense bars of light, move about. If non moving, they would light burn the plant in that spot.
Radiant guard will hold in heat. That can go each way. Be sure your cooling is sufficient. It's NOT CHEAP!