I myself am still very pleased with my PA800 + dated Yamaha PSR900, go figure !!!
regards
John Smies 
John,
In the UK we wouldn't consider any KB with built in speaker a professional bit of kit, so I can't figure it out, KBs with speaker are for home use, take the G70 it hasn't got built in speakers, ask the experts, they will tell you.. 

Regards
Tony