Soft synths are fantastic nowadays and getting better all the time. After all all the top synths today are digital and running soft operating systems so there is no reason a highend computer can't do as well if not better. By the time all music products such as synths and other keyboards make it into production the hardware has already been surpassed by current computer products hitting the market. But the unknown factor is not the synth software itself but the computer system and audio card that is being used to create the actual analog signal. Many computers suffer from electrical interference and noise and it takes a quiet system combined with a high quality audio card ( preferably with low latency drivers ) to compete with commercial synths and keyboards. Admittedly most computer musicians work entirely in the digital domain so electrical noise is not then an issue, but being able to play sounds live is an issue for many musicians.
[This message has been edited by Nigel (edited 02-25-2003).]