I’ve used Furuno on my boat for about 5 years, and it’s been fantastic. The radar especially is super accurate, even in bad weather. I fish offshore, so having reliable navigation is non-negotiable. The manuals are detailed too, and you can find them here:
https://manuals.online/furuno. They really help when setting up or troubleshooting features. Honestly, Furuno has earned its reputation with me.