[cisco-voip] Anyone user either of these call analyzers ?

[Tech Guy]

We are looking into evaluting these two products:

Hammer Call Analyzer - http://www.empirix.com/default.asp?action=article&ID=69

Etherpeek VX - http://www.wildpackets.com/products/etherpeek/etherpeek_vx/overview

Can anyone compare or recommend either of these?  Pro's and con's ? 
Any other solutions equal to or better to evaluate ?

Regards,
Dane