Well, keep in mind that you only get updates for 6 months. It says in the fine print:
"* Product enhancements covered by the SEO SpyGlass Search algo updates are offered free for 6 months since the date of purchase. When this period expires, these search engine related updates are offered on a paid basis. Without Search algo updates subscription the software is not getting algo updates and will not gather relevant data."
But even so, i found SEO spyglass useful. I used it a lot earlier. My version has now expired, but i am consider to pay for a renewal.