Web-to-Lead limit considerations before we choose it.

In Professional, Enterprise, Unlimited, Performance, and Developer Edition organizations, you can capture up to 500 leads in a 24–hour period. 

If your organization exceeds its daily Web-to-Lead limit, the Default Lead Creator (specified in the Web-to-Lead setup page) receives an email containing the additional lead information. If your company regularly exceeds the Web-to-Lead limit, click Help & Training at the top of any page and select the My Cases tab to submit a request for a higher limit directly to Salesforce.

When your organization reaches the 24–hour limit, Salesforce stores additional requests in a pending request queue that contains both Web-to-Case and Web-to-Lead requests. The requests are submitted when the limit refreshes. The pending request queue has a limit of 50,000 combined requests. If your organization reaches the pending request limit, additional requests are rejected and not queued. Your administrator receives email notifications for the first five rejected submissions. Contact Salesforce Customer Support to change your organization's pending request limit.