798c hd si combo or 898c si combo

as the title says which would you choose and why, other than screen size is there any difference ? both have si di and 2d. does anyone one have both in their boat ?
I would like 898 for the TM but not to sure if that is a wise place to put that much locator ( is si effective on the TM ?) or do you put the 788ci hd di combo up front and 898 on the console ?

tax return is comming soon and this year half gets to go toward fishing $2500 + :biggrin

thanks guys n gals for all your help

hot grease for your fish and cold drinks to go with them

i have the 898 at the console, nice unit, but if you got the money a bigger screen would be nice, the 798 is so small i think the si would be nearly useless, (my opinion), si can be used on the trolling motor but when you turn the motor it is really gonna distort you screen, but if you keep the motor fairly stationary and aren't jerking it back an forth it will work well. i wish i got back half of what you are spending of fishfinders! you can get two 898's for 2500. i'm saving up to eventually put another 898 up front. best advice i have gotten is to buy the biggest screen you can afford!

oh i almost forgot the TM will be a new 80lbs terrova ipilot if that makes any difference

again thanks to all

thanks gobbler, it took alot of hrs this year (3200 aprox) to get that much back .............. dam government ............... lol oh well

Looking forward to remarks. I was going to get 798 and decided to get 898 in about 2 weeks. as long as no surprises come up. BBG Marine has best prices I could find.

Here's an "un-talked-about" image size phenomenon in SI discussions...
Structure image ratio size ...SI vs 2d

In my 1197:
A brushpile that shows as the size of a golfball on the 2d screen...shows as the size of a quarter in the SI screen...

In a 798:
That very same brushpile would show as the size of a quarter on the 2d screen...but show as the size of a peanut in the SI screen...

Structure images are roughly 1/4 size in SI as to what you are used to seeing in 2d...And if you "split" the screen... Structure images are smaller even still...

Buy the biggest screen you can afford...Unless you want to look at "peanut sized" brushpiles...

Rickie