I've only used it so far as a headphone amp, so I can't comment on the recording outs (I'm sure they are up to par). I thought it sounded lacklustre in headphones until I changed the IR setting from "flat" to "edge" - which I think pushed a lot of the mids and treble to the front. It sounds fantastic to my ears now - very lifelike and responsive. If you're using it in a mix, the "Brite" and "Flat" settings might be useful, but as a solo instrument, Edge is the one.
I'm looking forward to being able to play all my high wattage heads without annoying the neighbours, and hopefully rediscovering the magic of some of them.
The I/O seems to cover everything you could need and you can load your own IRs. So far I'm satisfied with the onboard IRs - I'm not a "deep editor" once I have a few agreeable and inspiring tones I can use, and I found these in the first bank. I might explore that more in depth some other time.
Being able to play my main rig silently any time of day or night was my goal, and it definitely delivers that in spades.