Typically bar chart is the winner most of the time. Several reasons,
1. Readability dies in a radar chart
2. Details are hidden. User often want to see the details of where the numbers end up
3. If the chart has an ordinal dimension where the order matters like Jan-Dec time series then radar may be okay to find that odd time of the year where you lose on sales
4. If the chart has non-ordinal but named dimension that has nothing in common with each other like Regions, Departments, Sales Reps, you want to use a Bar Chart and Sort them by Y-Value to show performance
hope this helps
