Are Oakley Flak Jackets good to use under a catchers mask?

I am a varsity catcher. I use an All Star system seven catchers mask. Most of the fields i play at are positioned so that as i am catching the sun is right in my face. I need to find a good pair of sunglasses to wear underneath my mask. I have been using my Oakley M Frames with an "S Hybrid" lens and i have had troubles seeing while ripping off my mask fast. From what i have heard the Oakley Flak Jacket fits tight on your head and wont come off. What is your opinion? Do you think that Flak Jackets would be a good choice? If not please leave your opinion on a good choice in sunglasses. THANKS