Nuforce STA200


I am curious about the Nuforce STA200 amplifier  If anyone has experience with the amp it would be appreciated if you would share your listening impressions, both good and bad.  Some of the descriptions I have read classify it as a class AB amp and others a class D amp.  I am not technical savvy about these things, can a single amplifier be both? 
Thanks
George
jetter
mrdecibel or anyone else who may have heard both amps.  I noticed that Audio Advisor is blowing out their Parasound A21's due to the new model A21+.  If I purchase the A21, what and where do you believe would be the level of improvement over my STA200?  Two pairs of speakers are both 6 ohm, one pair being 85db and the other 86db.  I am using pair of SVS subs.  Volume is currently not a problem in my listening area. Thanks in advance for any input.
I don't think the Parasound A21 would better within power limits, but it has 3X the power into 8 Ohms and 5X into 4 which could make a big difference not only in volume but also dynamics and openness...I have experience with both but only own the Nuforce...
You should be able to find a used A21 and if you don’t like it lose very little on resale. But at that price there are the Odyssey amps and the...