This is very popular request for some sort of generic comparison.
Be note at the moment Burp Suite got two Edition, Burp Suite Professional (for manual and advance testing), typically install into tester machine, whether it is laptop or desktop, since it need interactive testing and operate by user. Another edition is Burp Suite Enterprise (for those who looking for automated scanning and scheduling, off course, this need to install into server for 365 continuous running. Due to use case is different, Burp Suite Enterprise do not come with manual testing that address with Burp Suite Professional edition. Both edition is license with unlimited website, target, URL or web application. For Burp Suite Pro is license by per install basis. Burp Suite Enterprise is single server and matter for how many agent. Default come with 1 agent already for the server to perform automated and scheduling scanning. For customer required “concurrent instance” than need to license additional “agent” to install into same server, or volume of “agent” install in different box or location, but “centralized” manage.
For direct compare with Web vulnerability scanner that license by per target, website, URL or web application, it offer significant cost value performance. In particular for customer with lot of website, URL, web application or or target. The simplify one off install and unlimited scanning way offer cost value performance that practically can not be compare at all.
Feel free to contact us if need further assistance on the subject matters.