I agree that there's room for improvement, but they're so much better than the alternatives for 12V power.
- No exposed conductors
- Genderless, allowing any pair of powerpoles to mate, and allowing any DC device to feed or consume power from any connector
- Impossible to connect with wrong polarity (if wired properly)
- High current (45A) mating surfaces wipe themselves clean with every connect/disconnect cycle
- Stay together by themselves reasonably well, but easy to disconnect without too much force when desired
I've installed them in my vehicles, and use them instead of those infernal cigarette lighter plugs, which were never designed for 12V power. The lighter plugs are too big, and have a spring that attempts to push the plug out of the socket. I use powerpoles for 12V devices in my camping trailer. All my 12V ham radio gear uses them. I also use them on 12V battery chargers, inverters, tire air pump, chargers for AA batteries that are powered by 12V, chargers for cell phones, a small automotive 12V Peltier refrigerator, and probably a few other things I'm forgetting. I've bought a boatload of them, and I put them on virtually every 12V device I own. Now I can plug anything into anything, and use any 12V extension cord for anything.
The genderless feature is very nice for DC power, and it's one of those things I never realized I needed until I got it. I'll never go back to male/female DC power connectors if I can help it. I put two powerpoles on one end of a cord, and one on the other, and now I've got an extension cord which can either carry power to two devices from a supply, or which can be inserted between any pair of powerpoles that's already connected, and carry 12V to a load. I can put one powerpole on a 12V AGM battery, and it works well when discharging the battery into a load, or when charging the battery from an AC supply. And I can even insert a load between the supply and the battery.
You're right that the corners are sharp. They're like lego bricks, and anyone who has stepped on one barefoot will remember the experience. I also dislike the fact that it's possible to mis-assemble them, though it's not hard to avoid that. Finally, I'd like some easy way to positively lock them together, and I wish there were good cheap panel-mount and PCB-mount versions (I'm aware there are ways to mount them in a panel or on a PCB). But those are minor quibbles.
Expensive? About a dollar apiece in quantities of 10, or 70 cents or so in quantities of 100. Where do you get lighter plugs/sockets for significantly less than that? Or any other high-current connector, for that matter?
I haven't found a genderless DC connector that I like better.