I wholeheartedly agree with ifitsoundsgoodlistentoit. I picked up an A400 for £100 last month and must admit it compares well with my Plinius 9200. In fact, I'd say it probably delivers 60-70% of the sound of the Plinius for about 3% of the cost, which I think makes it an absolute hi-fi bargain and makes that extra 30-40% of sound quality look bloody expensive!
In terms of value for money I think you'd struggle to find better. I also picked up a Marantz PM66SE-KI last month for comparison and the A400 bettered it no contest. Don't get me wrong, I love Marantz gear having had a CD63-KI in and out of my system for over 13 years (I bought it new), and the PM66SE-KI is a good amp but it was outclassed by the A400. My girlfriend, who's normally completely disinterested in hi-fi, even commented unprompted on the clear difference (I won't repeat her exact words lest some die-hard Marantz fans get bent out of shape).
My only caveat would be not to use the A400 with overly bright sounding speakers as it could prove fatiguing over time.
Hope this helps.