I talked to Costantin for almost an hour yesterday. Very nice gentleman with a passion for all things audio, especially classical music. When comparing the Qualiton A50i to XP200, he said that both are excellent amps with the same house sound. XP200 is more versatile with more power, but the A50i has more tube-like qualities when it comes to midrange (more liquid, according to him), and the highs are a bit sweeter. On the other hand, the XP200 has better control over the woofers owing to its 100 watts of power. Both have excellent holographic qualities, and unlike some other modern tube amp instances, they are not trying to mimic solid state, which is a good thing IMO.
It’s a tough call, but so far I’m leaning heavily towards A50i, although I’m sure I’ll be happy either way.