I've used them and they work great when you get the wicking/filler right. Out of the box with the stock filler they worked
flawless for me on 2 atomizers. My other atomizers were finiky with them. Seems things have to be exactly right and any tolerances in the filler/bridge, fitting etc can cause them not to wick properly.
I loved them with the stock filler on my atomizers that worked with them...bigger bridged attys work better I've found. When it came time to replace the stock filler it was hit or miss with me replacing it and getting the amount correct for proper wicking.
I went back to my BD Moded Ce2s. They work great for me without the hassles.