It seems impossible you can't find recommendations on this site! I think JL and Wet Sounds are the two most prolific for speakers. I'm a big fan of JL, have used them in two boats, zero issues, great sound.

Fusion is the most popular recommendation for head units.

Amps are all over the place...I used Rockford Fosgate but they are not quite fancy enough for most CSR members And, for the record, I did have one pop after 2 years. Clearly a lower end unit but easy (and cheap) to replace.

 

When I replaced the stereo on my 280 I went with the JL audio 650 series speakers which were a direct bolt in. I also went with JL audio for the amplifier and replaced it with a JL 400/4. In the 280 I added the JL bluetooth adapter and left the clarion unit in place.

In my current boat, I went with the Fusion 770 and remote units. plug and play type install, nothing too difficult aside from running the remote wire to the unit from the helm. I also added a NMEA 2000 network to handle the other remotes which is a little more involved, but you can asses if you need to go down that path in your application.

 

@stg099 Please can you advise which route you used for the remote wire as I am considering the same setup?