AdInsight Clarity
1 websites

AdInsight Clarity offers both free and paid options

http://www.responsetap.com/

The system saves visitor information so it can report on every keyword that generates telephone enquiries. This way you are able to get complete accuracy with your call tracking and drive further improvements to your ROI

VS

Nextag ROI Optimizer
3 websites

Nextag ROI Optimizer is free to use

http://nextagsellers.blogspot.com/2010/02/roi-optimizer.html

2 Feb 2010 ... The ROI Optimizer is one of the most important features that you can implement to understand the performance of your account. What is it?

Market Share by Top Websites

2 In terms of market share, AdInsight Clarity is clearly lagging behind, losing to Nextag ROI Optimizer in all segments.

Websites Categories

1 Nextag ROI Optimizer has better usage coverage in more websites categories. Including Lifestyle.

2 AdInsight Clarity hasn't got a lead over Nextag ROI Optimizer in any websites category.

Geography

1 Nextag ROI Optimizer is leading in most countries, including United States.

2 Nextag ROI Optimizer is leading in United States.