Feature Comparison to SugarCRM and VtigerCRM

I'm trying to compare the working features between ZohoCRM, SugarCRM, and VtigerCRM.

Yes, I realize Sugar is open source and also not open source, Vtiger is open source, and Zoho is not open source. I also understand that some are hosted (on-demand) and some are on premise. These seem to be the typical comparisons when looking at the three products.

I am only looking to compare the actual features each product offers.

Any help would be appreciated.

Thanks.