Behave Pro.. worth it or not?

[Matt_Patman]

Morning

Through an annual licence justification and purge exercise, I found out today that my team have accounts with Behave Pro. 

I started to look into what it is and it appears to be a decent addition to Jira.

I would really like to get some thoughts from other users...
* How does it work - Is it separate or an add on/extension?
* Does anyone else use Behave Pro alongside Jira?
* is there an additional fee or do we get it free as we have a Jira license?

What are your overarching thoughts? including - is it worth the fee?

Thanks,
Matt