Although PA Soft/BMW Scanner is a good tool, I advise people from getting the PA Soft/BMW Scanner 1.4.0 as the first and only tool for a number of reasons.
1. You need a computer to use PA Soft.
2. It does not provide much real time engine management data from what I have been able to gather.
3. Cannot monitor fuel trims.
4. Cannot perform data logging or graphing.
5. It does not provide Emission Readiness Code status.
6. It does not work on other make & model cars.
And I am sure there are things as well that I did not cover.
The issue is with these cars you really need a decent scan tool, and software like PA Soft and INPA to get a full view of what is going on.
The other problem with PA Soft/BMW Scanner 1.4.0 is many novices get their software up and running and then "see" their car has dozens of codes and then they start to worry and get excited about the codes and errors they are seeing. This tool at times can provide too much information and you have to understand what is critical and what may be bad/old data from a simple problem like a low battery.
But the tried and true handheld scan tool is something you can easily keep in your car and have ready at a moments notice, where the software based tools require you to keep a computer with the interface in the car when you travel.
Again, you really need more than 1 tool to get a full view and access to data on these cars. PA Soft/BMW Scanner 1.4.0 is a good tool to have, but may not be the first tool I recommend purchasing.