I tried on both the mips and non mips giro foray. I found the fit on the mips version a lot better. The mips does take up abit more space incase your are between sizes.
I tried one on the other day and the medium fit well but I'm not sure if it was the MIPS or non MIPS version.... I've ordered the MIPS version so will see how it fits, can always send it back if it's too small.
Cheers! It turns out the MIPS version of the foray isn't much more at all so might as well go for it.