Hey @Johannes_r , I am new around here but I think @Kevin_Z  can help with that (check his last post).

Sorry for the off-topic but how are you enjoying that kit?

More specifically, how is the speed reported in the software, compared to what you get on the end device?

@peetezaah can you link for me which post you mean exactly? I didn't find more specific information around here yet.

To answer your question, I'm using TP-Link Powerline products for quite some time now. I experienced some issues with the previous 600 Mbit series, concerning sudden loss of connection between the adapters. But it seems that this problem doesn't occur any more with the 1300 Mbit series.

Concerning the speed I can say, that there's a huge difference between the theoretical value of 1300 Mbit and the actual speed. In my installation I'm getting results between 30 and 600 Mbit - in the software. I can't really make a statement how reliable those numbers are, since I never really benchmarked it properly on my own. Just from a very general point of view I'd say: Yes, it's at least not too far from reality.

@Johannes_r after clicking on his username I noticed you can't actually see threads started by the user, which is weird.
Anyway, it was this thread that he himself started on the sub-forum we are now (Powerline Adapters). It's not helpful for your query, but at least you have someone you can ask stuff directly about this software. 

@peetezaah thank you. I still have hope to get some more information from TP-Link. I guess the main problem is, that only someone from the development team can really answer my question. They should know the exact specifications, but no idea if this can be shared. I also tried to contact the support already, but their answer wasn't helpful at all.