Lucky2Bhere,
I sent you a detailed email. The SD1 does hav a sequencer (16 tracks) and Sampler plus some feautres and sounds not found on the SD5. That said, the SD5 has the new sound board with authentic guitars and organ voices, improoved sax, horns, strings, better styles and some new features not found on the SD1 (plus the internal amplification).
Check your email for more details.
Thanks,
AJ