How much do you value a specific feature or characteristic of the storage product you may purchase? This is a tough question. Some of the products are different in that one may offer a special feature or do something in a different manner that seems better. Vendors will highlight these differences and you may make your choice because of them. Did the product cost a little more because of those features or special characteristics? If you got those did you give up something else?
The tough part is figuring out what the value is to your company (and to you getting your job done, on more of a personal level) for those features. If you're not going to use them, then you should probably disregard them. Usually they aren't really free. There's some tradeoff for price or complexity or weakness in another area.
We often ask customers we work with to apply a weighting factor to several different areas of a product. Doing a comparison to figure out which product meets the need becomes a little easier then because you can evaluate and score a product in particular areas and then apply the customer weighting factor to see if it's really meaningful and come up with a composite value. Really, the weighting factor is common sense: How much do you value this particular feature or characteristic? It's worth the effort.