When you want to do your investment tracking - first thing you need is a list of your transactions. And full list of transactions includes deposits, dividend payments, etc. To enter all these transactions is not an easy task. With
Portfolio Slicer you will start building your transaction history in Excel and if later better products will be released or something happens to Portfolio Slicer, you will be able easily transform those records into different format.
Portfolio Slicer supports many more stocks than google finance and it can produce much more advanced reports that you could with google spreadsheet.
Disclosure - I am owner of Portfolio Slicer.