Well, when it comes to consistent braking action I don't know that electric have anything over surge.
HOWEVER that is not the only issue.. .As I drive across Nebraska on I-80 while noticeing a fine mist and reading the temperature at the front of the rig off it's built in sensor (33 degrees F)
A good and proper electric braking system gives the DRIVER full control of the towed's brakes. You can apply them independent of the MH brakes, and you can disable them (or as good as disable them) if you need to And you may well need to under the conditions above because a sliding tire has no traction and may try to pull ahead of your motor home thus messing up your nice new RV Underskirt and letting damage happen to your towed (OK, so now you know why I was in NE, Pender NE, where the OX turns BLUE)
(At least part of the reason)
And, yes, when it comes to driving I am a control freek. Control good, no control not good And with surge brakes,, You have no control, it's all up to the hardware
I've been towing a surge brake dolly for 3 years with 3 motorhomes. Over 35K miles I've had zero problems. I hook it up and forget it, knowing that if the tongue of the dolly in coming forward on the ball the surge brake will be applied. The harder I brake the harder it brakes. I've been in ice and snow twice with no problems. I've had it in the Rockies, Smokies and Appalachian mountains -- no problems. I don't know anything about electric braking systems.