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? 
I have had no problem powering either my 6 ohm 89db or 6owhm 85db speakers, but neither are crazy loads.  Also, not sure if its because I have a tube preamp or not, but no obvious gain problems.  Maybe just lucky.
Thanks for the comments guys I am looking to power 86 dB proacs and had started to think maybe the amp wouldn’t be able to power them sufficiently. I am considering an nad m51 as a pre.
I'm running the STA200 with PMC OB1 (87db 6 ohm) with a NAD M51 as the frontend and have no complaints. The amp will drive the speakers louder than my neighbors would be willing to stand.
Audio Advisor has demo’s on sale for 399.
Without ever using the stock cord, the STA200 always sounded musical, grainless, and airy to me.

Some amps will measure great but don't sound *right*. Lots of negative feedback will do that. Trust your ears and how you feel when music plays through the gear.

Into my 4ohm Maggie 1.6s, music or TV *always* satisfied. It never clipped even with room correction low bass boost (TV optical only) using a deq2496. Only with crazy or clipped blu-ray effects would it clip and clip HARD (quakes, explosions, choppers closeby etc). Never while playing DTS or Dolby demo tracks tho.

I swapped in a 650W @ 4 ohm Crown Drivecore 2 instead and the same conditions would also cause clipping, but gave me more headroom.

I miss using it but love the power the xls2002 delivers. I'll find use for the STA200 somehow, it sounds so right, sweet, coherent, in or outside the room. Maybe bi-amp with the Nuforce on top (assuming I can match  gain) but will see first how my new vintage Soundstream DA1 does full range with the maggies.

Wishing musical nirvana to all.