Yes that is true. Most of those gauges have to many gauges and dont mean anything.
I am currently working on getting a wide band o2 sensor. They are not cheap though. About $600 is what I will try to target. This is an actual unit that will give you an actura lamda reading. Its great for tunning your fuel computers.
I dont think that the autometer or that unit you have there Ekewl will work. Reason being is that the srt works off a 2.5V setup, instead of the .9-.1V. Im yet to research this but this is what someone posted alreayd. I think it was mike?