As for A2Z
Personally I Cant Fault them so far :), Sales team are great and really quick, and Keep you well informed.
Haven't any install yet, but don't expect any issues there either.
A2Z are always the first call i make if we need anything
I had quite a bad experience with A2Z at the last school I worked at...
Placed quite a big order, delivery was a few weeks late, monitors were completely wrong - glass screen TFTs ordered - normal screens delivered, then before incorrect screens had been collected, a second delivery of incorrect screens arrived - needless to say they were sent packing.
Never used A2Z since, pretty sure I never will again.