For technical info, read the other reviews.
My only regret is that the sounds can't be edited.

UTILIZATION

For me, the keyboard is excellent.
I tested, among others, the Yamaha P140, whose keyboard felt too "heavy" even in light mode.
It's extremely easy to use and the manual is really helpful for certain settings that are a bit more complicated.
The response is perfect, it is exactly what I was looking for.
I haven't had the time to test midi.
Impeccable manual. That said, there aren't many settings to modify...

SOUNDS

I was looking first and foremost for a good piano sound, and I'm really satisfied!
The sp200 offers no less than 12 pianos from classical to more "artificial" ones.
Personally, I prefer pure sounds with the metallic sound of the strings. One of the pianos is really satisfying.
The other ones are OK and the classical guitar is also pretty good.
The strings are rich but not realistic (too "stringy," in fact).
So it's not bad when it comes to sounds.
The excellent keyboard and response make it a real pleasant piano.

OVERALL OPINION

I got it 2 weeks ago.
I love its looks, weight (40 lbs) and ease of use. The effects, chorus and reverb, are awesome, as well as the setting of the keyboard.
I only regret that the sounds can't be modified and I don't like the sustain pedal at all, it's really cheap.
As I said before, I tested the yamaha p140 but I didn't like its keyboard.
I was ready to buy a secondhand roland RD500 that is very comprehensive and whose keyboard I like a lot.
I think the sp200 has a very similar keyboard (although I haven't played an rd500 in years, so maybe I'm not being too objective...).
As for the value for money, I found one for $700 online, shipping and handling included!!! I think I bought the last in stock. I got lucky...
I would certainly buy it again, especially at that price!!!
Even if you buy it for $800 in other stores it's a great deal, IMHO.