I recently purchased software from WallingDataSystems, all correspondance was done over email which I was a little apprehensive about to start, but it proved a delight! Everytime I had a question there was an answer within hours (we are on oppositte ends of the globe) and even after making stupid mistakes myself in getting the software working, the representative was always patient and helpful. A big thumbs up to these guys, made my life a lot easier.
Cheers