Mastersound tube amps: 300b vs Dueventi

Hi everyone,

first of all, thanks in advance for your time. I'm new to the world of audiophile gear and recently fell in love with the sound of the Audio Note IZero amp paired with some Devore speakers. It had a magical, tube-like quality that completely captivated me. However, as much as I enjoyed it, I felt the amp was very basic—no remote, quite entry-level, and it seemed a bit cheap overall.

Now I’m exploring alternatives in a similar price range (~2500 EUR), and I’m open to looking for second-hand options if it means finding the right device. I’ve come across two potential candidates from an Italian brand called Mastersound - recommended by a popular shop in Berlin that prioritizes only brands with a strong "musical" attitude (let's say the same Audio Note style). Both would fit my current speakers setup:

1. Mastersound 300B Compact
   • Not the latest model (about 8 years old)
   • From a private seller.
   • The previous owner mentioned they "improved" something internally and replaced original components with higher-quality ones (?)
   • 65% discount over retail price
2. Mastersound Dueventi
   • Latest model.
   • Available from a reliable shop.
   • Fully original and inspected.
   • ~50% discount over retail price

On paper, the 300B Compact seems to have the edge over the Dueventi in terms of design and specs, but I’m concerned about the risks of buying from a private seller and the modifications made by the previous owner. Are these potential red flags, or could this still be a worthwhile purchase? Is there something I am overlooking?

I’d love to hear your thoughts, especially if you’ve had experience with either of these amps (or similar ones).

Thanks in advance for your help and advice!