In fact we prefer it that way. You can try the system out yourself for 30 days FREE.
There's no risk for you, just register for an account and wait for an activation email. Then follow a link in the email to set up your password. After that, click through to your account page, create a booking system setting up some initial aircraft on the way. Your booking system will be online in under five minutes.
The system is not limited in any way just because you're using the trial period. You can create fictitious members, aircraft or instructors and experiment with how to make a booking, book out an aircraft, record the flight details and even write up some training notes.
If you decide to keep the system running, you can purchase a subscription from your account page. Otherwise, your system will be taken offline automatically at the end of your trial period.