G2 reviewers of Tenable Nessus overwhelmingly rate it highly, with most giving 4.5 to 5 stars, suggesting strong satisfaction despite recurring cost concerns. Many G2 users describe Tenable Nessus as cost-effective relative to competitors like Qualys and Nexpose, praising its accurate scanning, extensive plugin library, and actionable remediation guidance. However, pricing of Tenable Nessus is frequently cited as a barrier, particularly for small businesses, nonprofits, and individual consultants. Several G2 reviewers note that year-over-year price increases are eroding value. The consensus is that Tenable Nessus delivers premium value for organizations with dedicated security budgets, but may strain tighter budgets despite its capabilities.