Cheap units are fine. You just have to learn to set the sensitivity and depth range. I have never had anything nice. I really liked the eagle 320 and 480 units. If you learn to work them you can find your boo. Learn to set it manually. Took me a while to learn this, but I did. My favorite unit was like 90 bucks on ebay. It also was an eagle...had a gps in it.
Its been a while...but I remember setting it up with depth towards the bottom of the screen....then use a 1/8 ounce jig and get my sensitivity to where I can just see the jig moving up and down. If you get your sensitivity to sensitive you'll get ALOT of trash in the screen...
Do not use the fish id...and do not use the auto settings. You'll have alot better luck. Spend some time in the electronics forum. Post some pics...they'll help you out. It will make your time on the water alot better. Your boo is there. You just have to get your graph setup.
"But if serving the Lord seems undesirable to you, then choose for yourselves this day whom you will serve, whether the gods your ancestors served beyond the Euphrates, or the gods of the Amorites, in whose land you are living. But as for me and my household, we will serve the Lord.” Joshua 25:15