Men are becoming more au fait with the notion of choosing engagement rings, and women are becoming less discreet about how they show off their new diamond rings.
This has a serious implication for men. It means that now they have to work harder to impress their future spouse, bearing in mind that she will be (consciously or otherwise) comparing the ring you give her with every other ring she has seen her friends get and that it is no longer such a big deal to have chosen a ring all by yourself.
One sure fire way to avoid this situation is to get custom engagement rings designed. In this day and age where absolutely everything from furniture to perfume can be customised to your exacting standards, it is possible to get a custom ring created.
Why is this solution you are looking for?
Well, because of the time, effort and expense involved custom engagement rings will instantly win you brownie points, almost irrespective of whether she actually likes the ring or not.
Additionally, custom engagement rings will therefore be seen as being in a league of their own so can't, in all fairness, be compared to anyone else's.
The general rules about shopping for unique diamond engagement rings still apply though. Work out what size ring your partner needs by pinching one of her other rings for measuring, try to design something in accordance with her personal style and taste and try to stick within your budget.