I see folks say this sometimes, but really surge brakes work well for what they are. They don't require an onboard electrical system, they are load adjusting, and they are low maintenance. It's more about the driver and their competency towing than it is about the system. As opposed to an EOH system adding more points of failure, especially in something like a private use trailer that will almost always see little if any maintenance.
We will have to agree to disagree. Been hauling boats for many years, big and small. Most with surge brakes. A few years ago I converted my twin axel boat trailer to EOH disc. A world of difference, reacts faster then surge and stops quicker. Also can apply trailer brakes on trailer to stop any trailer sway. Maintenance is about the same, check fluid and pads. Only additional would be keep electrical connections clean. I have never talked to anyone who switched that hasn't said they wished they had done it sooner.
Padraig