Bought this with the SH01A & wasn't disappointed.
Initially thought I would add value to the SH01A having the keyboard to go with it. Didnt want to have to spend more a few years later on the K25M if it was discontinued. I didnt think I'd use it as much, but the K25M is very useful for any boutique that has a step sequencer, as you can tap in notes so easily & the sequencer will follow on until you play it back. It definitely makes inputting notes more organic as you can play out an idea before inputting sequence data.
I find the keybed very good. It's no grand piano, but there was s a responsiveness to the keys that other units this size don't have. I've played chords & melodies with it & it does the job. Doesn't feel rattly or cheap.
The construction of the K25M is really good. 2 tough metal sides. Decent plastic base. The SH01A feels really solid inside it. The one con is the way you can tilt the boutique up with the SH01A. This is done with a small plastic 'foot' - similar to what you'll find on the back of a photoframe. Would be better if it had of been more robust. Also, its a little awkward to get the cable from the SH01A into the K25M. The Box acts as a good case for synth & keys. A good buy IMO.