I have used this app for many years and financed BlackCat for several upgrades. This time I managed to receive an upgrade without paying for it. The brushed aluminium interface is a no no for an App like this. When complex information is to be displayed, it should be displayed in a functional and eye pleasing manner and one that permits the user to immediately grasp the meaning of the colours. Brushed aluminium adds nothing but distraction to the meaning of the interface. The app is comprehensive in its content and is therefore useful if you are lucky enough not to have to upgrade it.

I agree with all posts regarding the upgrade policy. It is not worth it hence although the interfaces are also overdone here are free alternatives:
http://www.jschilling.net/sw_smellomints.php
http://home.tiscalinet.ch/marvin/iMass/iMassHelp.html

or just search for Period in version tracker and take your pick