I own the instrument for few months now and found out some series issues:
some of the keys has a loud unusual "clicking" noise that ruins the playing experience - sent a video to thomann and they approved it is an issue.
One key makes a different unusual noise,
Speakers are ok until i move the slide to the mid-level, then, an annoying buzz/distortion appears only when playing the B note (probably related to the frequency of the note).
Thomann labs fixed all the issues and now everything works as expected.
In any case, the instrument sounds good and feels good but the quality of the mechanics and the speakers is poor.
Didnt expect that poor quality from Kawai, very disappointed.
Buying a digital piano this day and age is a very hard task.
So many wonderful products for entry-mid level players from Yamaha, Kawai, Roland, Korg and more.
After endless hours of reading and watching reviews (and some playing) of Yamaha p125/515, Roland FP30/60X, ES110 i decided to go with the New Kawai ES520 for the following reasons:
First and foremost, The Piano sounds, they are top notch and almost cannot be beaten (Shigeru Kawai SK-EX and Kawai EX grand piano).
Internal speakers are ok, not too loud but delivers great quality.
Action is definitely on the light side of actions but the playability experience is smooth and enjoyable and this what's matter most to me.
you can also tweak the instrument to give you "a heavier feel" with the touch curve.
The key action is a bit noisy when the keys are coming back up after being pushed down.
Bluetooth audio gives you a great opportunity to easily playalong with your favourite music.
There are numeros ways of tweaking and configuring the instrument to sound exactly how you want it with the Virtual technician from Kawai App or the on-board user interface.
This 14.5 kg instrument is even lighter than Roland's entry level DP- The FP-30X. (The FP-60X which is the comparable mid-range model from Roland is 19.3 kg!)
If you are looking for a beautiful sounding Piano with smooth and realistic action you will be very pleased with the ES520.
If you Don't care about the weight and are looking for a full featured workstation, check out Yamaha's DGX-670 or Roland FP-60X, they have tons of sounds and other cool features at the same price bracket (give or take).
All around, it is a great instrument and Thomann offered the cheapest price i could found.