Good but not that great

To be fair, my site had initially been infected by malware prior to installing WordFence (Free version), when I run the scan, it identified few obvious unknown files (.default and .bt) found in WP-Admin and detected alternation in the Functions.php file but could not identify a malicious file in the root directory of WP (jjquery.js) which baffles me because no .js file should be in the root folder of WP, so this right here makes me wonder how efficient it is, meanwhile the Firewall seems to be doing an ok job.

Is it worth the Premium license? Not convinced imo