I have a set of Vetter soft bags that I used for years. The main advantage they have is they go on and off quickly. With a few adjustments, they can be moved from bike to bike, too. And they are better than nothing.
The big disadvantage to soft bags is when you are traveling in crappy weather. I have hard bags on the BMW and I fitted the CBR with GIVIs. I haven't used the Vetter bags in years. Once you've used hard bags for serious traveling, you probably won't want to use soft bags again, except for casual use. Hard bags are a little more secure, too. The soft bags are easier to swipe.