I was tired of dealing with a sagging rear due to extra weight, I'm glad I went with the high capacity coils. I believe AEV nailed it with these, you definitely need 37's with flat fenders though.
If you're going to be doing a roof top tent, I highly recommend the 4 1/2" HC AEV springs. I just completely redid my entire drivetrain and upgraded to a currie 44/60 setup and 37" tires and it rides great and handles the extra weight without an issue.
I used their standard angle brackets and they seem to hold very well. The only thing I didn't like was the m5 screws and nuts. They're somewhat small to work with, but after awhile you get used to them.
I wanted to try the 3 way connectors, but I never ordered any. I would expect those would...