Hey....
I picked up the Lowrance H20 a few months ago...also bought the Navionics Gold XL3 Chip, which covers all of Georgian Bay, Trent Severn Water System (with all connecting lakes ie-Simcoe, Couchiching) Ottawa River and much more...
These are Hydrographic charts with all the depths, shoals, etc...
Currently, there are no chips (that I have found) that have Hydrocharts for Ontario INLAND lakes..
There's plenty of software out there with lakes, rivers, roads, etc....but I don't find that useful, because that is what a map is for...it's the actual depths and knowing where you are that sold me!