We use the AirMagnet suite as our tools for surveying and troubleshooting. I know the others work also like Ekahau and Motorola. You just have to learn the right way to use the tools in order to get correct data. The only thing I don't like about AirMagnet is the fact that some versions seem to work better than others. depending on the laptop and build, you might get slightly different readings.
Always make sure whatever card you use you test before you survey with. Ive had issues with cards reporting a higher than normal noise floor skuing the data collected.
"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin