I’m heavily relying on the MBS plugin for some list operations; with FMP16 two of them have been finally implemented natively. I’m talking about SortValues and UniqueValues.
On my MacBookPro retina with 2.3 GHz i7, 8 GB RAM and 256 GB Flash storage (Late 2013) and running Sierra 10.12.5 beta 5, on a 15’000 elements list, the MBS plugin calculates these in around 20 ms, while FMP16 needs an average of 3300 ms apiece.
Notice that I am using the MBS List.xxx functions, not the QuickList.xxx ones, which are faster.
My test database is attached, however if you are not running FM16 with MBS plugin there’s no point in downloading it. But if you do have that setup, I’m curious to know if you see the same pattern I see.