Hi Bob,
I have the previous generation in the smaller screen to the model you are considering (Echomap Plus 75SV) and have been using it for the last 2 seasons here. I upgraded from a very old greyscale unit and so I cant directly reply to your Humminbird comparisons but can tell you what has worked for me.
is the unit capable of self mapping like HB autochart?
Yes - QuickDraw is the Garmin name for this. Useful feature for the backlakes w/o map. However need to let the unit power up and acquire GPS lock before you can dig through the menus to enable the recording and needs to be re-done everytime you power up if you want it to be recording new data.
There is an online portal where you can either upload your contour data for public consumption, or grab data posted by others and import into the unit :
https://connect.garmin.com/modern/quick ... fullScreen
Unsurprisingly there is not a lot of data for Eastern Ontario posted so I never did try pushing/pulling from the internet portal.
if so does it require a new card like HB?
Does require a microSD card yes - nothing special, any generic $10 SDcard will do. I seem to recall something about a zero line card in the Humminbird ecosystem, but that doesn't exist in Garmin.
can you superimpose the self mapping onto the formal map in the unit?
Yep. But be aware that some places where the included map and the actual data (eg: a smooth, linear transition from the surveyed point at depth 20 to 0 feet at shore, but the reality of the water is that is a steep drop from shore to 20ft) that can produce some pretty funky looking map combos.
ease of operation?
Seems fine enough to me. The menu structure of the software to get the setup configured is not the most intuitive, but the basic things like sonar and mapping aren't impacted much by that. The touchscreen interface is ok but the CPU is a little under-powered IMHO so the UI can get a little laggy in response in some views.
customer service any good?
Never had to contact them so cant comment there.
likes
- 2D traditional sonar is a huge step up from my previous unit
- Screen visibility is excellent even from a distance/angle.
- Quickdraw maps since I mostly fish unmapped lakes.
- Colour coded depth ranges on the maps/quickdraw content.
dislikes
Think I covered some of those above but for completeness :
- Nesting menus for setups can be confusing
- Ice transducer setup is $$. due to that I havent converted it for hard water.
- wish I knew how to read/use the sideview sonar. I suspect this is operator issue not the unit itself, its just not that useful to me.
- built in maps dont have very good coverage of the Ottawa River (at least in the west end) for some reason which was disappointing since that is one body of water that I really did want to have good mapping of due to the number of hazards out there in the murky river waiting to eat a prop. At least with Quickdraw I have built up enough of a base for the areas that I visit now over 2 seasons. This portal may show you what the built in maps have for your target lakes (
https://lakes.garmin.com/ )
I cant compare the Garmin unit to the Humminbird - maybe someone else who has ran both can.
Fox