Hey, I used to work with a retailer selling Advanced Acoustic (up to around 6 years ago). They were by far the leader in returns / repairs. The worst were their CD-players and all-in-one devices, especially those with tubes. They look attractive, but it's really all China-made stuff.
That being said, I own an X-A160 solid state poweramp. I had to have it repaired within the first year of ownership, because some part failed, but after that it's been smooth sailing as a daily driver for the last 7 years. It doesnt hiss, is plenty powerful and has nice VU-meters