The manual is quite good. Detailed enough for most people to learn basic synthesis from and for those more experienced, it covers everything necessary to operate the synth. Since I grew up playing the organ, not the piano, the keyboard feel to me is excellent. I'm just not used to the fully weighted keyboard and the semi-weighted feel of this synth is really quite nice. Full 64 polyphony.
Effects are pretty good.
Chorus, Reverb, Overdrive, Leslie, etc. They are simple to use when you get the programming aspects of the synth down. Full MIDI implemintation. 10 Sound is very individual. I try to base choices on items that can replicate the sounds used in the music I play.