Lukitoh,
George Kaye, Bluezplayer and Starkeeper tried the EM55 and answered your 1st query. Don't be impressed by the quantity of sounds/tones. IMHO the sounds are similar to the EM20 which I own. EM20 list about $550 cdn, maybe $300 U.S. The EM55 lists at $1100 CDN, $995 U.S. IMO the sweet voices on the PSR2000 is superior do any sound on the EM55. I prefer the acoustic piano on the Rolands instead of Yamaha's, but that could b just personal preference (I'm not a piano player).
Starkeeper