Having replied to several others I owe it to you to make a post QRT response.
One modern behaviour that distresses me is the default of asking someone, anyone, for basic technical advice. For antennas the ARRL Antenna Handbook is very good place to learn about antenna basics. Minimal maths. Reading references seems to be a lost art. Even Google will supply more info than you can read in an afternoon. Check the credentials of the writer of course.
Not checking previous threads and resurrecting yet another dead horse is part of the same disease.
On this post G8TMV has pointed to a fine posting by AA5TB on making the EFW work. Bookmark it. You can then refer the next enquirer to it. I do not feel motivated to extract the numbers from it.
Asking about peoples experiences and preferences is of course legitimate and to be encouraged.
I should start a new thread for this but WTH. The best portable ATU’s do no better than 90% efficiency, dropping to 50% on some frequencies. Google is your friend for this. No need to ping me for making a statement without a spreadsheet and diagrams.
Broad band preset matching efficiency is inversely related to size. Should be obvious - small core, thin wire, unknown quality capacitor, etc.
When I build Baluns and rf transformers I make 2 and connect them back to back to check for loss and frequency response. Educational, especially if you can get two commercial ones for test.