MUSE HiFi M5 Ultra thoughts?

[Lion03]

Hi, I'm new here and I'd like to know what you think of the MUSE HiFi M5 Ultra.

I'm looking to upgrade from my FiiO BTR7 and am interested in trying something different. The M5 Ultra looks very interesting because it has tubes.
I've never had a tube amps before, but I'd like to know what it sounds like. My other favourites are the Topping G5 and the FiiO BTR17.
So let me know what you think of them.

Thanks!
Lion