well......
I began with Lowrance. I have 2 Lowrance units on my bassboat. They are older models tho (b&w) no gps, and they are anhhhh.......ok.
I really don't use them for finding fish.....mostly just depth. They are several years old.
I have a close friend that has high $$$ Humminbirds on his bassboat, and he loves them.....no problems.
I spoke with a local dealer, and his response was that Humminbird had taken the market for the past few years......due mostly to customer service. Other reasons were difficulty in using units.
Right or wrong, I began looking.
I knew I wanted color, and gps, and I wanted to be in the $300 range. Then I began looking at reviews of the unit, Amazon is a great place to read reviews, but they only showed 2 reviews for the Helix. So I Googled reviews for the unit. I found some other favorable reviews (don't remember where).
Now....the unit I will buy is the Helix 5 DI w/ GPS. The GPS has an internal antenna and the DI stands for "Down Imaging". This, as I understand it, will show fish within a structure.
Now I probably will not fish from our new tritoon boat, but, with GPS, if I happen to find somewhere that I would like to fish....I can GPS it, save it to the card, and revisit when I have the bassboat in the water.
I began looking at BassPro for pricing, but it appears Amazon has a little better price. If you don't want or need the "DI" function, it is cheaper. If you don't want or need the GPS....it is cheaper still.
That was my rational, price range, ease of use, color, gps, will work with lake map software, has 5" viewing screen.
A problem that I will encounter is.....where to put it. I could install as an in dash unit (which I would like), but the steering wheel will make it difficult to see....

......so.....now I am checking out "Ram" mounts to get it up higher....but....I would have to remove the unit after each use to be able to put the cover on boat.
I have never owned one, but, I understand that the Garmin units are good units, easy to learn to use, and hold up.
Hope this helps.....pb