Sounds like a decent plan but I would second the idea of leaving it in and sampling at 10k miles and see what the report says. If your corolla is indeed spotless inside (including the piston oil return holes) then it would be interesting to see how far you can really go on the Amsoil with sampling.
How often do you usually check oil level?
Since you just put the Amsoil in (sounds like that is what you did based on your post), I would recommend checking the level regularly to see if it takes time to settle out.
keep us posted with the progress.