For $250 that sounds like a good deal. I've never heard of Performance Teknique. I went to their website to find more info on that amp and half the links on their page do not work. Not a good sign for a long term investment but at $250, if you get 2 years out of it I'd still call it a deal.
One thing I would worry about in this arena of digital input amplifiers is the DAC that is on board. People pay alot of money for a stand-alone DAC so I can't imagine the onboard one will be much better than those found on mid-level head units. The best solution is to find a stand-alone DAC or a processor that accepts digital input. There are solutions from Alpine, Zapco, and other big name brands.