I just bought the 787 c2i and have been impressed overall.

Satellite acquisition is a bit slow when first started and GPS is a bit sluggish to show heading changes, but these are not big minuses in my book.

I did get the Navionics maps package with the unit but I have not been on a lake which is covered by them yet.

Only reason I didn't go with the 797 was money. It was just a touch too much for me to fork out at the time.