[polyphemus]

"Do you know what single function the convex follower performs that the flat follower doesn't? It's more of a band-aid that compensates for a lack of something than anything else...and that advantage is compromised by the use of an extended ejector, even if it doesn't touch it."
This is a good one,so going in reverse.The extended ejector flips the case out
sooner than the standard one so the convex follower works on the premise of
better support for the last round both during loading and extraction.
A convex follower would behave like a round still in the magazine so earlier ejection would minimize any support from below.