I have a size Large RED HiFi, white-off white color, and i use it with my Black/Gold Crest phenoms - looks great and fits even better - absolutley not even the smallest gap in the forehead area, and very little space on the sides - good combo.
only thing is, Phenom straps have the buckle in the back, which happens to be in the center, right where the goggle clip on the HiFi is located - the strap buckle doesn't exaclty slide easily underneath the clip, however i just put it over the clip and its fine - i guess you could always just take the clip off if you really wanted to, or force the buckle under it - not a big deal.
Go for it.