There are two schools of thought about HVAC/R tools
One side says that it is most important to understand the fundamentals and that fancy diagnosis tools can lead to reliance on them. The other side points out that without convenient access to the data that good equipment provides a technician is limited in what they can fully diagnose and test.
We agree with both
First, understand the fundamentals. Use and understand basic tools and the math and logic that the trade is built on. Then you can start to build your arsenal with high quality, accurate and well designed professional tools that help you do a better job at getting it right the first time.
No toys, no gimmicks, no technology at the expense of common sense. Just good, solid tools so you have the right tool for the job at hand.