You are correct no sounder or speedo strictly navigation. I have a 546s on my Boston Whaler works great , screen is just a little small, but a great unit Good luck and be careful

My 478 has a setting so they dont roll off the end when the mem fills up.

What is the sounder? On my Android Navionics app I have speedo and depth alarm sound set. (min 6')

It's a fancy depth finder with a screen and a alarm, how does app work, it doesn't have a transducer anywhere on the boat, I wonder where it takes the depth from, hopefully not where your holding the unit vertically.

With the sounder they install a transducer either on the transom, in the bilge or on the bottom of the hull, mine's going in the bilge.

Oh, I didn't know the Garmin hooked up to a transducer.
The app is just off what has been charted. So I would be nervous with tides, sea levels and accuracy when it was last charted.

I looked into the ipad/iphone thing when someone mentioned it and they don't give half of the info (speed, depth, low tides, channels, etc.) I'm looking for and they're not as accurate as a GPS, when I'm scooting along at 60mph I want the most accurate and fastest info I can get.

Thanks again.

Would the iPad be able to hook up to your VHF radio for DSC?

I don't have a installed VHF, I'm probably getting a good hand held for minimal use and emergencies.
I don't have any plans on heading out 20-30 miles out into the gulf, mostly intercoastal and occasional KW run.

The garmins are available without the "s". The sounder feature. The depth finder that came with the 382 works fine. The GPS is very accurate at 80mph in the keys. When I look at the screen and see a channel marker with a number Its reassuring when I look out where it should be and.....there it is, right where the gps said it was going to be! I just wish it had more built in memory. All the places we have explored with this 382 should stay in the memory!! Loosing tracks is bad....guess its the same as getting old..HMM

Fossil Fuel what are you replacing your 382 with. Great looking boat and awesome set up. Had a 382 w/525's loved it