L'Oreal's EverCreme cleansing conditioner had that effect on me (MAJOR headache), but I haven't had an issue with the SM Y&B. I haven't tried the mask yet, but I use the poo and conditioner regularly. They do smell strongly of gardenia, similar to CJ Curl Rehab's coconut-gardenia scent. I happen to like it alot, but if you're sensitive it could be a problem.
CJ RM just didn't do anything for me, but judging from the board, I'm an exception in that regard.
I've got 2 rainchecks from CVS burning a hole in my pocket, and I'm tempted to get both the yucca and the purification masques. I'll post a review if (who's kidding whom, when) I do.