best used HT receiver for 200 or less?

HI All,
I'm helping my 18yr old put together a low-cost music system. What's the best USED HomeTheatre receiver (DD minimum, DTS a plus) for $200 or less? It must have a Digital input. Coax preferred but optical is OK.
Thanks and happy listening!
HANDS down, the Onkyo TX-DS575X or no X.

$200 is the going rate, DD, DTS, 5 channel stereo, 6 channel analog ins, plenty of digital ins, all discrete power, THIS IS THE WAY TO GO!!

I agree that the Onkyo's represent good value.
Sherwood Newcastle 945MKII is another option