I beg to differ with you dude. I've got the Marcus Miller bass samples in my Roland and when played with good technique and through the proper rig, it sounds exactly like a live bass. I was on a gig one time with my old band. Our bassist couldn't make it so I had to do bass and quite a few people were fooled until they came in and didn't see a bass anywhere.
I have to agree, with much reserve. I heard a guy recently who was playing a bass patch on his keyboard... he is also a bass player, so he played like a bass player would with an actual bass, and I was amazed at how authentic it sounded. I leaned over to a friend of mines, and said, We can't let our board players ever get a hold of that patch...LOL!