You didn't mention voice editing, so consider the Yamaha PSR-S550B...a nice little arranger...a bit more loot than the GW-8, but it offers:

Keyboard: 61 Standard size keys (C1-C6) with Touch Response

Display: Large Backlit Black and White LCD (320 x 240 dots) displays notation, lyrics and chords

Voices:
- Total Number: 774 Voices+22 Drum Kits
- Compatibility: General MIDI (GM) & XGlite Compatible
- Piano Voice Quality: Stereo High Resolution
- Sweet! Voices, Cool! Voices, Live! Voices: Dedicated buttons
- Dual / Split: Yes / Left, Duel
- Drum Kits: 22 Drum Kits
- Polyphony: 64 Note

Auto Accompaniment:
- Styles: 176 styles
- Variations: 4- Variation A~D & Fill
- One Touch Settings: 4 per style
- Registration Memory: 8 x 8 Banks
- Music Database: 500 setups by song title

Digital Effects:
- Reverb: 36 types
- Chorus: 45 types
- DSP: 239 types
- Harmony: 26 types

Sequencer:
- 16 tracks to record your own songs (15 Melody + 1 Chord)
- 5 User songs +10,000 Notes

Real Time Control: Pitch Bend Wheel

Auxiliary Jack: Phones/Output, DC in 16V, USB to host (MIDI In/Out), USB to device (optional storage devices), Sustain

Amplifier: 12W + 12W

Speakers: 12cm x 2 + 3cm x 2

Power Supply: PA-300 Adaptor (included)

Dimensions (W x D x H): 37.2 x 15.8 x 5.1 in. (945 x 402 x 130 mm)

Weight: 16.5 lbs (7.5kg)