I would give up the entire tach for a temp gauge.
nope.. I love the mechanical tach needle. Even-tough the needle is probably driven by a digital input, I still prefer the physical display to a fancy graphic.
I definitely would not want the tiny, digital tach from the new mazda 3.
Fdew, your dreams can come true with an android head unit and an OBD dongle, or by hacking the infotainment to mirror your phone display.
Another thread on here shows some guy in Russia mirriring his I-Phone on his mazda 3 headunit.