I was just making my statements... Regarding not being perfectly flush, my 3.Ai are perfectly flush... Thinness more likely than not will affect fit, but not too much. I get a deeper fit with the 4.Ai (and I thought I had a deep fit with the 3.Ai :p). As for waiting to make my decision (I can say the same to you regarding the 900s), I use the headphones for at least a week before reviewing (and at least 3-4 days with extensive use before comparing).
I reckon you got lucky with the 3.Ai ;) Then the fitness is actually a handy thing all though insertion depth on these is not actually do dramatic although i do like them a little deeper. Dont you worry mate, i gave the 900s two days on there own when i got them and continued to use them even more building up the comparison but brought in the 4.Ai a lil bit and i am still using them as review soon, i know what i am doing :D