With all the MAJOR issues in Generation One, I was looking at tfwiki, and found this. Well, does that help anyone? Because, it doesn't help me, I'm still confused.
Devastator still seems bigger than Astrotrain so I'm gonna have to say no. But, it's Transformers; the definition of defying logic for fun and profit. The only anything which makes any sense in size is alternators and it has its own confusing problems.
This is the scale chart Takaratomy is using to make masterpieces, thus mp-12 is in perfect robot scale with mp-10