Two that are very close to your price range would be a lowrance elite-5X HDI. has a color display as well as down imaging. Another to look at would be the hummingbird Helix 5 SI. The bird has built in GPS with down imaging and side imaging and they have great customer service. The only thing I can say is think about the direction you may go in the future before your purchase. I am a very avid walleye guy and I would never skimp on electronics.
For myself color display is a must to help pick out fish very close to the bottom. GPS is a must so I have lake maps on my unit not only to locate depth changes but to save my butt while running in un familiar water.
I have always been a diehard lowrance guy but switched to hummingbird last year for their side-down imaging and to link my trolling motor to my electronics to help stay in the depth I want to fish. The bird, minkota link system has made my fishing experience a lot more enjoyable.
