Well I received 2 of these little amps from MassDrop yesterday, shipping to the UK was FAST. I ditched the stock tubes immediately and put Russian 6P1P-EV power tubes & Telefunken 6AK5 driver tubes in.
In comparison to my original MiniWatt S1, the APPJ mini2013 has just a little more power, and definitely does not run as hot. I'm running it full volume, with a passive 48 step shunt attenuator in between the DAC & tube amp, some parts of the chassis are slightly warm, unlike the the 'very hot' chassis on my MiniWatt S1
Sound wise the APPJ mini2013 (after 2 days listening) is darker & fuller, whereas the MiniWatt S1 appears to have more clarity and feel brighter


That's my 2 day overview.
I'm hoping that 'in time' the clarity will improve, with a little more separation in the detail, only time will tell what it will be like once I put some more hours into burning it in

If anyone else bought this APPJ mini2013, it would be interesting to know your thoughts & initial impressions too ???