HB 788ci HD vs HB 597 ci HD

I am looking at buying a new depthfinder and the two units I am trying to decide on are the HB 788 ci and 597 ci. Both have the 50 channel gps and the same size screen. The pixels are the same and the power outputs are the same. Some of the features you get with 788 are advanced features that I don't know much about. Could some of you electronic guru's tell me why the 788 would be better over the 597. The price difference is roughly $130. Is it worth my money to get the 788?
Thanks for all your help,
Ringo

hi the bottom line is that you can have 2 cards in at once one for maps and one for memory

i just bought the 597 saturday

Another advantage would be if you want to link this unit to a second unit. The 788ci HD will be able to do this while the 597ci HD will not be able to.

thanks for the help guys. Now will just have to decide if the extra $130 is worth or not.
Ringo

Ringo..if you can just gather up a little more $$ (well a little to some ..is a lot for others)...

And step up to the 798ci HD SI Combo...

SI is the most amazing thing your will ever invest your hard earned money in....

Rickie