sleev-les

The current depth finder I have is always way off. I know they aren't perfect, but I'll have it read 1.1ft and not change, then I had the thing read 250 ft. The waters I'm on, I know pretty well so I know I'm not at 1.1 ft where I'm boating. I want to buy a Garmin GPS with the built in sounder and then just get the transducer for it. Are the newer units a little better as far as accuracy? Im looking at touch screen and about an 8" screen. I've seen a couple models and they are pricey, but I'd be mounting it where the old unit I had was, located on the passenger side dash. I have room for a bigger unit, roughly 8" x 11". Mainly looking at how good these are or what is better than the readings I've been getting with the current depth finder.