I like how accurate the product is when guessing and searching email address. Using Zoom Info, it's a little easier to use but the accuracy is not there as far as getting the correct information. Sales Navigator is extremely accurate.
I don't love that you have to manually type in the person's email to confirm it is correct. While Zoom Info was down, I strictly used Sales Navigator to find out whether the persons information was correct. Like I mentioned before, it's extremely accurate but very time consuming.
With MapViewer you can download maps from online web mapping-services (WMS)
and you can add and modify map-titles, scale bar, legend, inlet-maps etc. One of my personal highlights are the drawing-features: You can easily add arrows, rectangles and so: No need to use an extra drawing-program like its necessary with many other mapping-software.
Mapviewer supports a lot of different import and export-formats, e.g. Shapefile to name just the most common industry-standard. On my personal wishlist are SQLite and POSTGIS, which currently are not supported. Of course you can export production-quality-maps in various formats.
You can also digitize and edit new features with Mapviewer e.g. create new polygons, line, points , break apart polygons and lines, union polygons etc. There are various projections and datums available. Mapviewer also offers GIS-functionality: you can create buffers and query boundaries even on different layers that meet specific criteria.