I would suggest caution using FLCH with Flap / Speed combinations if high on approach. It can lead to extreme rate of descent close to the ground and gets messy if A/T stays in idle Thrust eleveator mode, rather than thrust speed. (Sorry been a little while since I flew it so the exact modes are getting hazy).
I found hitting 5000 at 20nm, then reducing FPA to 1.9deg and decelerating/ configuring worked a treat for a "normal" approach.
Also from memory takes 800ft to slow from 280 to 250 in FLCH, so if you get 800 ft below the vnav profile then at 10800ft hit flch/ 250kts it works out nicely.
Good ship
