I originally bought these for my tragus's but I ended up putting them in my helix and they work perfect. My double helix is only 4 months old but the titanium jewelry it was pierced with seemed to really irritate and kept causing large bumps. I decided to put my 7mm u hoops in to see if the swelling would go down and immediately within a few days the swelling was way down, I went and put in the 5mm u hoops and now the bumps are barely even there and my ear is so much happier! The diamond heads are a bit of a bugger to get screwed in but you just have to be patient. The customer service is also very good, they have been incredibly helpful.
Excuse the daith, it's not very old.