Thanks for your comments, guys.
@TheLegacy: It would be great if we knew the people who decided not to get our product but we don't have the means to get this information. We're hoping to get advice from everyone, really, not just our clients. Thanks for your thoughts.
@rhetorical: We fully support our products. After all, we made them. If you're referring to customer support, our clients simply have to submit a help ticket on our
website and we'll deal with their concerns in the soonest time possible.
Anyone else who can recommend other good billing systems? Comments or advice are very much welcome.