Landserf is great for finding images other sites might not always have. It has data about shading that I find very useful for my job. Compared to other solutions we use, I do find it is not as full featured, but it gets the job done. Review collected by and hosted on G2.com.
It is not for the beginner GIS user and it can be clunky. It doesn't integrate well with design tools we use but the raw data can be exported. I would like to see it work together with Aurora or similar solar design tools. Review collected by and hosted on G2.com.