I have the watch smartcast...pretty cool...I usually have to switch the sensitivity to low so it will only read bigger fish...and not junk on the bottom...once I forgot to switch the sensitivity and i was fishing this sunken tree and the fish ID came on...and I thought a fish was hiding in the tree....after 15minutes I finally figured it was some trash like can or something...as I threw a big heavy jig in the exact spot and the fish icon didnt budge a little...LOL...also turtles will show up as fish on the LCD too...but over all its good...I use it on small city lakes...and sometimes it gets choppy and it still reads the bottom really well...the green sonar unit has good weight to it...so it casts a mile...but the battery cannot be replaced...but heck it lasts 400hours plus...the battery in the watch is easy to replace...can go to Savons and get it for $4.50...althought the unit comes with a spare battery....
One thing I dont like it that the settings on the watch unit always resets to default whenever you shutdown the unit...so like everytime you power up you have to switch on the fish alarm etc....
The green sonar unit looks like a little submarine...but underneath it has to metal contacts that turns it on whenever it hits the water...but I think it also makes it look like a green topwater frog lure...LOL I was worried when I casted it into the slop that a bass would pounce on it...