I've been thinking of updating my now old MFD, so I have been doing some shopping in preparation of if it dies, or has a problem.
My two contenders are the Garmin or the new Raymarine Axiom.
The Garmin is nice, but lately you're stuck using only their cartography (Charts). I don't know how responsive they are to reported errors of the charts, nor do I think they have as much detail as other charts.
The Raymarine Axiom seems MUCH quicker to draw on the screen, update during moving, and is generally more responsive when using it. It also allows for Navionics charts. I found the Navionics charts to be a derivative or related to the much loved Bizer charts of the lake. It also seems to have some more detail than the Garmin charts of the lake. I also like that Navionics is very responsive to chart errors when reported to them. They often will publish a fix to their charts within a week or two of a report and then you can download the new chart with the correction. You can review the Navionics coverage of the lake online to see if you like it:
https://webapp.navionics.com/?lang=e...y=q%60ciGvnxrL
This sounds like it would be a no-brain choice for the Raymarine, but the Garmin seems to have a lot of transducers available, so depending on what you want or need, you may want to choose one or the other. I would love to use the Garmin 'forward looking' Sonar transducer, which can show rocks and hazards up to 300 IN FRONT of your boat, but it's a very pricey option, but certainly cheaper than any fiberglass, or I/O/Propeller repair!
Most people wills say to choose the chart that you like, and then buy the MFD that supports that chart. Further blurring the line is that Garmin recently (last year) purchased Navionics, and this implies that Garmin may support Navionics charts some time in the future. I recently contacted them to ask if they will support Garmin, but their answer just recently was that 'we're just now thinking about this, but can't give an answer as this time'. So no one can predict if all Garmin MFDs will support Navionics, or if only certain future models will allow it.
These days, I think most MFDs will serve basic navigation needs. Good luck with your choice!