I have both, good quality gauges like defi for example are a lot faster than a good quality odb connector but the odb is very handy for checking various stuff/resetting codes on your phone and using for video overlay etc.
I have defi gauges + BT1 Blu tooth connector, dash command etc etc.. the later is no where near as fast as a Tatrix cable either (though fixing a laptop to the dash wouldn’t be very practical
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