Ive tried a few different amazon tools to help with keywords and sales metrics. Overall AMZShark has a good UI and a decent price structure. I really liked the niche scout tool as it was able to put up info on one page and allow me to decide if other niches were attractive targets. Also used the super url tool, even though it's unclear if they work anymore. Regardless, the software offers a very easy way to add a super url. Overall i've been impressed so far as it's been a fairly robust platform to aid in my Amazon selling.