Well...
I think every woman should have some what of a say in their ring. After all they are going to be the ones wearing it for *hopefully* the rest of their lives.
That's not to say that the man should not have final say on what ring he choses to buy. But I think every couple should at least go ring shopping.
My Fiance and I have been together for 4 years. We have been to many jewelers. We both did our research on diamonds and metals before he purchased the ring. Having said that, my fiance knew exactly what he was looking for before he even bought it.
I knew what my ring would look like before he proposed to me, but I had no idea when he was going to buy it or when he was going to propose. That in itself was enough surprise for me!
And I know how ugly and hateful this is going to sound, but I am not a jewelry person to begin with, so if he would have gotten me a ring that I hated, I might have had a Carrie moment. Of course we all know that it's not the ring itself that is important, it is the symbol and sentiment of what it represents. So with that being said, I would have been happy with or without a ring, but thankfully I was fortunate enough to get the ring of my dreams.