As an unapologetic technologist, I typically tell people to cut through the sales speak, ignore the glossies, and pay attention to the technology that's being pushed -- not who's pushing it or how.

Lately, I've been having second thoughts about that advice.

Storage isn't quite a commodity market, but it's getting there. Any of the top five primary storage vendors today can deliver perfectly capable products to meet your organisation's requirements. Often, the biggest factors in your buying choice hinge on considerations that have more to do with the vendor's policies or character than with the technology itself.

So before you buy, by all means check the specs of competing systems, but make sure you answer the following five basic questions as well:

1. Are they pushing product or offering solutions?

When you invite sales reps into your office, the ball is in their court to collect the information needed to provide you with an accurate quote. If they start talking about what you should buy before you even tell them what you have or what you're planning down the road, how can you trust that the solution will serve you well?

They may well have the best overall product, but the chances you're going to receive it in a configuration that addresses your needs is pretty much nil unless they understand your infrastructure almost better than you do.

2. What is the vendor's real-world reputation?

You did ask for references, right? Hopefully they were offered and you didn't have to twist anyone's arm. But what sort of references is the key question. Make sure you contact at least one or two long-standing customers that have actually used the vendor's support and are willing to talk frankly about that experience.

You can learn a lot more about what a vendor is like to work with when you speak to someone who has used several generations of their hardware -- and of course, the closer the reference's requirements are to yours, the better.

It goes without saying that references are almost always handpicked, so it never hurts to do your own research. You'll find horror stories about every major storage vendor out there, and some of those are worth taking into account.

3. How much will it cost you to scale up?

The data explosion is all about dealing with continuous expansion. But with most storage vendors, the best deal you'll ever get from them is the first one.

Down the road, when they know you are stuck with them, it can be a different story, so ask about add-on costs before you buy. Chances are you're probably buying at least one or two different kinds of disk for your storage solution, so have them give you quotes for various add-on options now. Nobody will really guarantee future pricing, but having the conversation up front will help keep them honest later -- and you'll find it easier to compare the costs of the solutions you're reviewing.

4. What is the TCO over the long term?

Very few organisations acquire a new primary storage solution and keep it in production for only three years. Even if it's rotated out of front-line production duty, chances are it's still active and doing relatively critical work through at least the fifth year.

Be wary of vendors that hesitate to provide you with quotes for five years of support -- or at least solid estimates of what years four and five will cost. The ratio of support to hardware costs varies wildly between vendors, and when you reach the out years, the differences can be even more stark. Be sure to factor in those costs.

5. Is your prospective vendor a good partner?

Enterprise purchasing bears little or no resemblance to a trip to Best Buy. Switching costs are high, so like it or not, you're choosing a long-term partner. You're trusting this company to ensure that the most important part of your infrastructure will to function well and lend itself to being scaled, with as little disruption as possible, as your needs change. Are you confident -- both via references and your own intuition -- your relationship will stand the test of time? Like marriage, it's all about trust.

If any of this advice seems obvious, well, good. You're ahead of a lot of other buyers out there. I've seen some or all of these points overlooked in the past -- with serious consequences.

Or perhaps you have your own favorite litmus test that I haven't covered here. If so, leave a comment to this article and share them with the rest of us.