Looks great! I was in the exact same boat. And if you really need to redo some wiring or add anything, all you have to do is unscrew the OSB and re-install when done
2 applications. The speedhide has a built in primer if I recall correctly. My garage needs some serious organizing but here's a few pics to give u an idea. I'll probably get the floor done in the next year or so.
First pic is looking in from the laneway with the front part empty.
Second is...
It was definitely latex which I rolled on. About the same size as your garage (750 sq/ft). Half of it has 10' ceilings, the other half has 12' to accommodate my hoist. I'll dig up what brand I used this weekend. Have a big garage clean-up planned so I'll post a pic after. :)
I have the exact same interior on my 3+ garage. Two coats of a really light grey paint and it looks awesome! The OSB loves to soak up the paint so keep that in mind.
Slads