As I have said before, my expertise is in English as she is goodly spokenated.
In reporting we run into this all the time. There are more things going on in this world than grammarians ever dreamed of. What we are dealing with in this particular situation is how to handle the plural of numbers (in digits).
Either is correct. Model 10s or Model 10's. I personally prefer the apostrophe, as I think it is more readable, which in my business is paramount.
Not unlike when someone turns a noun or adjective into a verb. Usually not a problem. But I have had more than one real estate agent testify that they final'd/finaled the contract. I go with the first one because, as I said, it is more readable.
Or would you prefer Models 10? That's what the book seems to call for.
Or we could let the singular and the plural be the same, as in deer, elk, sheep, moose, cattle, etc.?