makes it difficult to adjust on top of the mountain if I need to.
That's your problem.
I rode Burton est boards for the last 2 years, had no problems with them, own multiple and im stoked on the channel.
#1. The screwdrivers at the hill at the tool-benches suck ass.
#2. With my experiences with the EST, if it loosens on you during the day your screwed, every time you slide it around and shit re-mounting it snow, dirt, whatever else, gets caught in the binding when you re-mount it and it makes it so you cant tighten it down properly.
Mount your board at your house and leave it, take your "#3 Phillips" and crank down on your hardware as tight as you can. and Voila! your set. when you go up riding, double check and re-tighten it in the parking lot before you start your day. You should be set for the season.
I have never had issues with the channel. I guarentee you have nothing wrong with your board or binding.
If you stick with one stance and dont play around with it its gonna hold, once you touch it to "tool" with your stance at the top of the hill (nice pun eh?) its gonna make it a bitch to keep tight on the hill