The sound is very unique; it's not for everyone. From what I've seen the quality isn't the best, but you are paying very little for an excellent sounding amp. The guy who builds them did something I personally wasn't keen on, but we all have different ways of running a business. Basically, a customer had paid for an amp, and was explaining to some forum members how he was going to take some gut shots for those interested in seeing how the Jet City amps were modded. Hovercraft then apparently saw this and refused to ship the amp out. Instead he gave back the money. I think it was eventually resolved, and this all could be inaccurate information, but this is the Internet: home of inaccurate information, and home of paranoia.
I had a Dwarvenaut 20. It was stupendously loud and thick sounding. Actually louder seeming than a 60-watt Sunn through an Emperor 2x12 when I gigged both together. Definitely had more bite to it. Not much in the way of cleans or headroom, but that's not what they are designed for.
Tolex was fine on mine. The Jet City markings were a little sloppily removed, but I have little else in the way of complaints. Nial responds fast and is informative. If you have questions or doubts, just ask. He doesn't take money until you are certain you want the amp.
Edit: and "recycled" means he repurposes amps into being something else. A lot of them so far are Jet City amps with all new guts, speakers, and so on, but he's also modded Sunns, Hiwatts, etc. I believe.