Desktop/Software Management Solutions???

I am currently researching a number of desktop management solutions including SMS 2.0, LANDesk 6.3, ZenWorks/Manage Wise bundale, HPOpenView/Novadigm solution, etc. I have not found much research in the way of true product comparisons. Can anyone provide with non-biased rational why to choose one product over another. And/or give testimonial for a particular product based on past experience. Finally, if there is another comparable solution that is not listed, please let me know and point mein the right direction to research it.