When you can grow your lists to 1000 or more, you are going to want a healthy way to both manage and clean up your keyword lists.
On the whole, NicheBOT V2 does a good job of doing this. As far as keyword management goes, the interface is good, and the continuity between features is excellent. The only thing that annoyed me was that I couldn’t figure out how to combine lists (and remove the duplicates).
As far as keyword list cleanup, NicheBOT V2 on the whole delivers as promised. The only thing that it lacks (In addition to most other keyword tools) is that the appending tool doesn’t add the keywords with the appendages as new keywords, but just replaces the old ones. I want the tool to keep the existing keyword, AND create a new keyword phrase with the appended words.