Too many options, Advice welcomed

[BNC04]

Hi all, I've not been very active on here but read the boards often and would like to request some thoughts an opinions about what my next electronic purchase should be.

Currently I am running an eagle mono 320 at the console and an eagle mono 240 on the bow. These have been OK for the last few years but I’m thinking about upgrading. Right now I supplement the setup with a hand held GPS however I do not like doing that since the screen is small and in creating a way point mark takes to long especially if I see it while trolling. So I would like to upgrade one unit on my boat to start.

Periodically I’ll troll for a variety of fish but the majority of my fishing is done from the front of the boat jigging and casting for walleye and warm water fish. Most of my fishing is done on smaller lakes so mapping is not a huge issue for me though when traveling to some of the larger lakes in the area and having some maps may be something that I would find useful. I’ve never seen or used a mapping software so I’m not sure how much value they would add.

I listed my priorities in somewhat of a particular order.

Cost 600.00 range or less
Widest screen possible within the price range
GPS
Sonar
Color
Sunlight and polarized viewable
Ability to grow expand
Reliability
Ease of transferability. I will be upgrading boats in a couple of years to a 17-18ft aluminum deep V with a windshield.
So far I have been looking at the HBird 788c, Garmin 520s and Lowrance 522c

Thanks Brett