After downloading the PVS-Studio distribution and requesting a key to experience the tool, you'll get a fully functioning version, which will be working for one week. In this version, there are absolutely no limits - it is a completely full license. When filling out the form, you can choose which type of license you would like to try: Team License or Enterprise License.
Differences between Enterprise and Team Licenses are given on this page.
If a week wasn't enough for you to get acquainted with the tool, just let us know in your reply - we'll send you another key.