When I was young I used to love reading Superman, Batman and Spider-Man comics. Oh, ok, I admit it: I still do! Anyway, I always thought their costumes looked really good: colourful, good for showing everyone your biceps and, well, different.

The trouble is, of course, is that in reality these costumes would be awful. Just on a practical level, where are the pockets? And from an aesthetic point of view, you only have to look at some of the people who wear such costumes for fancy-dress parties or protests to see how they show not only your biceps, but the lack of them, and your bulging stomach if you've not kept yourself in trim. I’m not being unkind here: most people would fall into that category because most of us don’t look like the airbrushed pictures we see all around us.

In other words, appearance in an ideal situation is one thing, but the reality in normal everyday life may be, and often is, something quite different.

We all know this, of course, yet continue to be mesmerised by new kit on display at technology shows or in the pages of glossy magazines. You cannot base really serious buying decisions simply on the basis of seeing a product in ideal conditions.

In my opinion, before you make any investment in new hardware or software you need to:

Ask the simple but crucial question: will this enhance teaching or learning?
Ask whether this will work with other products you have. The key thing to bear in mind is that a product may be brilliant in itself, but less so when used in conjunction with something else: you need to see the big picture (see next point)
Ask yourself if this purchase is in keeping with an overall strategy; I’ve come across schools which have several different online locations for storing documents, because over the years different products or services have been purchased with no regard to what was already in place
See it action away from the technology show or conference exhibition at which you first saw it
See it at work in a school which is similar to your own …
… And which has not had an investment of free training, expert visitors and tons of cash by the company concerned
See how well it performs in doing what you want it to do
Seek the opinions of other schools which have been using it for some time
Check to see if there are (independent) online forums about it
Try doing a search for <product name> sucks, as this can sometimes yield interesting results
Ask your Twitter community what they think of it
Find out if another product does the same or better job more easily or more cheaply
Explore support and warranty options
If it’s a significant amount of money, invite several companies to tender for the work, even if because of the amounts involved it turns out that you are not legally obliged to.

If it sounds like a lot of hassle, that’s because it is – but it’s better than disappointing everyone by buying stuff which looks great but which, in the cold light of day, leaves a lot to be desired in terms of practicalities.