The all-electric (what i think of as a 'ramp' type controller, since it 'ramps up' current to the trailer brakes at an adjustable rate) controller is perfectly adequate. This is what I used towing the '65 Globetrotter with the '59 Bentley cross-country, in the 1970's
I never once encountered a situation in which i wished the brakes performed other than the way they did. The 'proportional' braking available from the 'inertial' or 'pendulum' controllers is only approximately proportional, using the change in the forward momentum of the tow-vehicle's braking (in conjunction with a signal from the brake-light switch to initiate it). Lots of people love this type of brake controller. I find it a little too 'hinky' in some conditions, although i've never used one long enough to master its idiosyncracies. I'm still really liking the Ultima 2020 (i'm not a paid spokesperson for anything, nor do i play one on tv): http://www.go.to/jordanresearch Tuna