I rarely use it. Other tools give much more information i.e. Google Analytics. I would highly recommend using a supplemental tool to go with Marketo's SEO tool.
Agreed. The SEO tool is a great overview for Marketing to see a briefing of what's going on SEO wise, but in terms of setting SEO strategy, you should use another product and supplement the data with Marketo's tool.
I really like Moz for SEO purposes. They are one to the top thought leaders for SEO and their tools are pretty good too. You might also look at SEMRUSH. I use semrush for keyword research and tracking rankings. There are a ton of SEO/SEM tools out there. What are the main things that you would like to accomplish?
I want to accomplish optomizing websites, keyword research link builing and fixing the content on my websites. I have used Moz in the past I really like it.