19.76 miles, thats how long it took my Adrenaline 9's to settle in. This is my fourth run in them in four days, so I think I can give an adequate review of them. It kind of disappointed me that the shoes took so long to open up, they felt really narrow for the first three days I wore them. I physically couldn't go past five miles- my feet hurt like hell around the ankle area, but that might just be the way I laced my shoes.
I'm a severe overpronator, and a forefoot striker, and I will admit towards the ends of today's run, I defanately felt it. That said, the GTS 9 is a great shoe. Its my fault because I could really do with a shoe with more support, but since my foot is shaped so weired and the GTS 8 worked so well for me, I might as well stay with the Adrenaline line.
Structurally, the 9's are just like the 8's. They are a great combo of cusioning and support, but are a cut below the GTS in terms of quality. Honestly, and maybe its just the 9's being new, but if I could order the 8's again I would, I think the 8's provide a better overall fit.