One thing you'll find is that to get a good tool to datalog you'll have to spend money.
For instance, I have ScanXL standard from Palmer Performance --> http://www.palmerperformance.com/pro...lstd/index.php
Problem is for the things I wanted to datalog, they aren't SAE PID's. They are Ford specific. So I had to also buy the Ford Module add-on, an extra $90. But now I can datalog everything.
Now add up those costs and compare that to a used SCT Xcal. You'll find that your best option is to buy a used Xcal and download the free LiveLink datalogging software. The advantage is that LiveLink does not require any add-on's or extra money.
It does not matter is the Xcal is locked or not. All of them can datalog the same.