I just sold the 73 key version of the P125.
It has a good keybed, the instrument sounds are limited in numbers:-
Pianos are pretty good
Electric pianos good
Organs just OK
Strings, strained
Others not so good.
Onboard drum rhythms, very limited
Layers, limited to two
Splits, defaults with Bass.
An App is available to set up EQ, Splits, Layers etc and to save the Registration on the Tablet, there is no Registration save function in the DP.
Do note that that is just my own opinion based on having the DP for nearly 15 months.
What I miss is an auto accompaniment feature as found on an Arranger but I prefer 88 weighted keys so options are (1) Yamaha DGX 670 (2) Casio PX S3000 (3) Korg XE20 and this is one if the reasons I sold it, the other is that there were simply not enough instrument sounds.
The Yamaha DGX has hundreds of sounds, multiple layers, a good array of drum rhythms and auto accompaniment, plus its a brand new design. It can save Registrations in essentially a Songbook so you select the saved song and the DGX is all configured and ready to play. Also available with custom stand and three pedal unit.
Similar functions on the Casio and Korg, but take a serious look at the Casio, its slim, sleek and much smaller bodied and in a living room environment it may be the better choice.
Hence if having a backing is important to you, forget a P series.