While demoing the platform, trying to make a purchase decision, I uncovered two big flaws with the Contacts tool.
Firstly, you cannot save Custom Column Selections. So if I have segmented my Contacts into Leads and Clients, I am going to want different sets of columns for each segment (or "Tag" in this system). Even worse, whenever I add a new Custom Field it makes my current selection of columns revert back to the default selection of columns. So I need to keep customizing my column selection constantly.
Secondly, and this is even more basic, you cannot sort Contacts by more than one criteria. For instance, first sort by Company, then sort by Name. Or sort by Transaction Type, then sort by Estimated Commission. You can only sort by one criteria which really reduces the power of the Contacts tool.
Overall I have found the Contacts tool to be really good, which is why I am so surprised it does not have these features.