The DI is IMO a must have up front. I currently have a 797cSI on the front, and it is OK but I rarely use the SI on the troller as it is so hard to keep it straight enough to get a good pic. I am actually thinking of selling it next year and getting a 800/900 series with DI (saw from ICAST these are coming out soon) as a replacement so I have a bigger screen up there.