Hello,
The difference is huge. You are comparing the cheapest debugger with the best in class.
It is like comparing VW polo and Bentley Continental.
For tests, students, low cost projects PE is fine. But for real development I recommend you to use Lauterbach.
You can rely on Lauterbach, basically I never find any issue in this debugger.
If you require it only for loading SW to flash then there is no big difference. What counts is the debugging environment and capabilities.
But, I think debugger vendors can get you most accurate answers on your questions.
Peter