Please note: I am not an experienced pianist nor a professional musician. I've played other instruments for 25+ years. I have all four XLN pianos (grand, upright, electric, electric grand).
To my ears, the sound quality is absolutely top notch. The samples sound gorgeous, editing options are vast with half a dozen microphone options, processing and effects. You can get an idea of sound shaping options via the pre-made sounds included with each instrument. I cannot notice any lag and the dynamic feel is very realistic, at least to me. I use a beginner Casio CDP-S100 as a midi keyboard with XLN. The standalone UI makes it very quick to start playing, although the user interface might use a bit of work. Looks outdated and some controls are a little bit annoying to find and/or use. Very minor complaint though.
Pros:
- sample quality
- sound shaping options
- standalone
- no lag that I can tell
Cons:
- user interface could use a few tweaks