I'm running Garmin finders.
I used Lowrance for years and found them very satisfactory for my needs.
I bought a Garmin Stryker 4 a few years ago for my lake fishing from a pontoon boat and float tube. I'm very happy with the Stryker 4 and would buy it again.
I decided to upgrade my 10 year old Lowrance elite 5 and elite 4 this year.
They both still function as they're supposed to but I wanted to move up in screen size.
I decided on Garmin because I know that many professional fishermen who make their living fishing use them.
Also I belong to another forum with several thousand members and the vast majority use Garmin chartplotter/depth finders and swear by them.
I purchased 2 Garmin Echomap UHD 93SV units for my 20' sled. I do a lot of bass fishing and have one on the bow and one at the helm.
I also fish for salmon and can put the bow unit at the stern when trolling with the kicker.


Honest disclosure. I haven't put enough time in using the new Garmins to form my own review but based on what experience I do have and many hours of watching Garmin specific YouTube videos I'm confident that I'll be happy with them.
They have a very knowledgeable and helpful tech support staff that can help with any issues about setup and instructions one might have.
The technology in todays fish finders is advancing so quickly like every thing else
That I believe you can't buy a bad depthfinder. Faulty...possibly but the capabilities of today's depthfinders are amazing and mind boggling to put it lightly.
Garmin, Humminbird, Lowrance, Simrad
Pick one, I don't think you'd be disappointed.
Go to the manufacturer's websites for the specs and so forth.
For the sound I'd recommend a 7" screen minimum size. 9" is better.
One doesn't need to have all the bells and whistles that higher end depthfinders come with either. A good traditional 2d chirp feature will be your daily driver most of the time. A chartplotter/fishfinder is a great unit and also a safety feature with the modern mapping capabilities in todays finders.
It also shows structural elements below the surface that fish are attracted to. Points, dropoffs, underwater humps etc.
YouTube is your friend on learning about fishfinders. Go there and do a search on 0the brand and model your're considering and you'll find more content than you'll have time to watch.
Coming soon to the "What have you done for your boat lately " thread are the upgrades I've done over the winter and early spring on my '93' Fishrite 20' sled.