have you heard about number of Gundam pre-sells ? It is just to have a better idea of the first day selling for this game.
I don't know the number. But according to some site, the number of pre-order of Gumdam Mosou is twise or three times than the one of VF5.
And, there isn't the news about first day sales yet.
But the obserbation that both of Gumdam Musou and Super Robot Wars W are sold very well becomes dominant.