Agreed! Bigger is better. GPS and map chip is a MUST! I use SI like my life depends on it but never even pay any mind to the DI. I am a troller only at this point. If your cranking SI would definitely help ya but if you know crappie habits in that lake and follow contours....at some point during a 6 hour fishing trip you are going to come across some fish trolling at 1.5-2.0mph just from GPS features alone. So....if you got the money GET SI. If not get HUGE screen 2d with GPS and get a chip. Leave DI at the house if you ask me. Alot of people like it but i dont find it useful in my methods. I have DI units on console and bow of my boat and never use it. Maybe I am ignorant.....but... I dont like im missing out on something.