Been looking into upgrading my graph from the 10 year old $100 unit I have on my boat now but not exactly sure where to start. All the terminology and specifics of these graphs are a bit lost on me but I am looking for something that has down imaging, side imaging, and GPS capabilities (preferably with topography/navionics compatibility). I'm still a broke youngster so my budget is around $600 max. I've looked at the Lowrance Hook models as well as the Garmin Striker units but wanted to get input from some guys who know more about these things than I do. Thanks in advance.

That's a tight budget, but take a look at the HB Helix 7 CHIRP DI GPS G2N. It has DI, but not SI. If you step up in rice to around $700 you can get the Helix 7 with SI and DI.

Helix is very user friendly. You don't have to be an electrical engineer to operate it. Garmin and Lowrance just aren't as good as HB.

Overtons is having a flash sale today....20% off
Good opportunity to get a 7" screen unit with SI that was perhaps out of price range otherwise

Thanks guys. For some reason I was thinking the Helix was a good bit more than that but I think that's what I'll shoot for once I can justify dropping the dough.