I have yet to see an 898 in person, although I expect to be receiving its non-SI cousin, the 858, in about a week.
The 898 is a slightly-smaller-screen version of the 998. It features a 7″ screen, the high-definition Side Imaging transducer, 50 channel GPS receiver, and dual SD card slots. It runs all the latest software (Down Imaging, Lakemaster compatibility, Switchfire 2D, new waypoint management tools, etc) and has an ethernet port for future networking. It’s a lot of technological power packed into a pricepoint that allows more people to get into a larger-screen Side Imaging fishing system.