This is my JF 15400, quality wise nothing to complain about, movement keeping pretty great time even with occasional wearing time, bracelet and general construction feels solid, comfortable and overall good. Decoration of miyota is pretty close although nobody in the know could ever be fooled in thinking it's the real deal, jewels look made out of plastic, rg rotor looks off all in all a remarkable attempt imho and flaws you can live with.
Bezel screws nice and sunken, polished details pretty good, date is perfectly centred but date font is wrong.
Tapisserie on the dial is too small, the dial in mine has a couple of printing issues with the white markers at 46 min and at 59 min and 1 o'clock marker a little crooked. Xtal and AR is very good.
Lume is strong but last too little. Thickness is still a bit generous but nothing major the watch doesn't feel bulk.
Put a gen rotor (or close back if you don't care) and a gen dial and you are good to go if you want to invest 3k+ to franken it up...gen dials are virtually impossible to find but from time to time on Ebay a miracle could happen...