A handful of exceptional Uchiha who manage to awaken the MS don't define the entire clan. They're outliers who can't be used to back your entire position on this matter.
Even then, I would say the more elite Byakugan wielders could stand against a Mangekyo Sharingan wielder.
Someone like Hinata would be tough as nails to put under a genjutsu because of her Byakugan and the fact that she trained with one of the Leaf's strongest genjutsu users as her sensei (Kurenai). I doubt many of the Sharingan's genjutsu abilities would have much of an effect, or at least require a bit more from an Uchiha than: "you are already in my genjutsu."
If Danzo can shrug off Sasuke and say: "Meh, you're no Itachi." - It would stand to reason that someone with the Byakugan and training could do the same.
I would argue that the Byakugan is, largely, superior in hand-to-hand combat because of its field of view. While the Sharingan may be like having ultra-fast vision that can view a TV screen as if it were a slide-show, it has a standard field of view that can leave one far more vulnerable to diversionary tactics and group engagements (why anyone would choose to fight "fair" in a one-on-one manner when the price of failure is death is beyond me).
I'd rather have the Byakugan as I feel it gives me more tactically and strategically relevant awareness - and information is the most valuable resource to any fighting force. You can have a million man army - if it's blind, deaf, and dumb - a division of a few thousand can tear it to pieces. Or, assuming you have two powers engaging each other, posessing relative capability within an order of magnitude of each other, the side with the superior intelligence and command network will win.