I would say that even gen submariners have Gaps in the SEL. It is particularly apparent when you have the watch in a light box with light blasted from all sides. This doesn't look particularly bad, but a side shot of the SELs where they meet the case would reveal any glaring issues with the recess.
All ZF BB that I have seen have good SEL reproduction compared to GEN. Quite often any looseness is caused by crappy Chinese spring bars.