Adeline:
The E Series is new and offers video integration which the C Series does not. Video integration displays remote video sources from CCTV cameras, entertainment systems. It also exports navigation video to video displays or remote monitors. I installed the C-80 system with radar, chartplotter, and fishfinder on my boat last year and love it. In my opinion the E series is overkill for a small boat. If you haven't already check out the Raymarine site; raymarine.com. Looking forward to Spring. Happy boating. Best regards, Rollie/C-batical