The biggest benefit is that it provides me with more insight into my clients' needs than I can gather from one to two face paced interviews! It's also great for getting referrals because people love knowing what their potential client likes/ dislikes etc prior they start working together (which saves time).
Sometimes some information are difficult or confusing so maybe need training in order understand everything fully but overall good software which helps us get better insights about our prospective customer base as well provide referral opportunities too.