This year I used Track Addict Pro connected to a Kiwi 3 OBDII, a Dual Electronics 10hz GPS and GoPro Hero 5. For lap timing and displaying basic data it is an excellent and simple budget system. It was always within 5/1000th of second with the transponder. Sometimes faster, sometimes slower. It might do more but I haven't explored it fully.I have Torque Pro on an android tablet pulling information off of an OBDLink MX+, but really just have it to clear a code if needed. My logging runs through Solostorm, which maps the OBD2/cambus information along with GPS info. The information is ok, but the refresh rate at 10hz could be better. Thinking of upgrading to a racecapture setup, again running through solostorm.
Don't really understand the logging for the sake of logging if you don't know what you were doing during that timeframe. The GPS data is important.
You are right about knowing what you are doing at the moment of logging. What I'd like to be able to do is show AIT, oil temp, oil pressure and boost information overlaid on the video. Secondarily, I'd like to be able to analyze each lap to show where I was weak or strong in each corner.