Most GM sounds do sound lack lustre. Point to any arranger that uses just GM sounds as its sound base and you will find in most cases an inferior sounding keyboard on every front whether we are looking at acoustic or electronic /synth sounds. I know you are not trying to tell me that most arranger instruments can/do use sound sources such as the 'Colossus'link you just posted. You and i both know thats simply not true. The link bares no relevance to the GM sounds found on most arranger keyboards to which my comment about sounding 'GMish' relates.