I got these on my cleric the other day... I really want to like them. But.... they scare the heck out of me after getting involved in a quest where I was surrounded by 8 mobs that weren't dying fast. Involuntarily triggered into madness, and it kept getting reapplied, over and over. (I'd been under the impression that you needed to activate the clicky to trigger it and then it could sustain itself if you kept busy.)
Granted, I'm durable even without active healing, between decent AC, DR, and my healing aura (or I'd have died fairly quickly) but it's a little unnerving no longer having my safety button there when I'm soloing (and if I'm grouping, you just KNOW it's going to trigger when someone is desperate for a heal and I can't provide it.)
If I knew then what I know now, I probably would have given them to someone else. I'm a safety guy and these things are dangerous!
How do other people deal with it? Just know that someone else is going to be healing you? Might try again with a really good tower shield + damage guard.