Agreed, the product does look very nice and to the junior DBA can give some good insight into what is going on with the server. In the past, I've used it to identify mostly CPU contention.

However, as mentioned, it can be a resource hog locally on your machine especially when monitoring more than 3 systems, I've noticed. Also, the software doesn't do very good when the server is having difficulties. The version I have used installs quite a few stored procedures directly on the server in question.

I have also used a product by Idera. Less resource intensive and can give excellent statistical data, but doesn't look as 'pretty'.