I use it - I've had it about 18months and it has steadily improved in terms of features and accuracy. The functions like load measurement, MAF reading, inlet manifold temp, proper coolant temp etc are all quite useful and the MPG and BHP/torque calculators are much more accurate now then they used to be.
I also got a cheapo Amazon adapter which works ok.
What I honestly don't know if it works at though is pulling error codes! Very early on I tried to use it to scan for errors and it said there were none, but I have no way of knowing if that was true or not! Some say it doesn't work properly for error code reading on some older cars particularly if you don't have a good adapter.