I had the P125 a few years ago and always found it a solid keyboard. The shape was a little unwieldy and it sat very high on stands or on my desk. So I took the plunge with the 225. I only needed an 88 note weighted keyboard that I could throw under my arm and perhaps one that isn't too bulky.
Speakers - Not as good as the P125 and this is down to the placement. They're at the back of the unit and I presume for use in a house where the keyboard is up against the wall and reflects the sound back. On gigs the sounds doesn't reflect back to you and it doesn't sounds as loud/clear as the previous version. It feels strangely disconnected. However in some cases I don't even need an amp for church gigs as the speakers travel well enough with the reverb of the environment.
Action - This is very subjective. I've been a Yamaha guy for a long time and my favorite action has been the action in the various Motifs 88 (ES8, XS8, XF8, S90, S90ES etc). The P125 used a common keyed the GHS. This is in a load of Yamaha keyboards and ranges from very good and useable (P125) to not so good (MODX8). Same keyed but I guess the chassis in which they are located has some impact on their finger to ear connection.
The P225 has a newer keyed BHS and to be honest it's not as good as the implementation of the BHS in the P125. The travel is slightly shorter and it tends to bottom out before you expect it to. I also have a Studiologic Numa 73 and its quite similar to that (Fatar TP110).
Now that being said I've played the 225 on a variety of gigs, solo jazz gigs, church weddings, musicals using the 225 as a controller and using MainStage on my MacBook. Im well used to it now and don't find it much of a compromise. Maybe it's my age but in previous years I would have probably sent it back as it didn't match the quality of the Motif 88, not that I expected it to but I would have hoped it was close. But those keyeds are too heavy to carry these days so it's a compromise Ive learned to live with.
Audio interface - A very useful feature I just connect one USB C lead from my Mac/phone/iPad and all my sounds come through the P225. One mono or two stereo cables from the P225 and Im good to go. Seamless and works a charm every time.
Sounds - Pianos are nice, a slight improvement on the P125. Rhodes is fine, Wurly is lovely with nice tremolo but it's baked in so you can't play without the tremolo. DX sounds are ok. I expected better from Yamaha. All others are fine, strings, clav etc. All playable. With the Montage and MODX you'd expect Yamaha to port some of these sounds over into this category. A bit like what Korg did taking stuff from the Kronos and using it in the Grandstage.
Other features - I haven't used the bluetooth or drums feature but they're fine. Some of the other features that are useful to call up quickly (transpose, local control on/off, speaker on/off) are located via multiple button and key presses that you'll have to print off as they're hard to remember. You can do these via an app but that's just another piece of equipment you'll have to use. Their compromises that you'll get use to at this budget.
All in all a good keyboard, that's an improvement on its predecessor in terms of size and weight but the action and speaker placement are not an improvement.
