Which one is better?

 

I've heard mechanical are more accurate, but they are more of a pain to hook up b/c you have to run the vaccum/boost line all the way to the gauge.

 

You mean manual boost controller or electric boost controller?
All depends, especially on preference.

 

I have had both. The mechanical one, after some time, would not go back to zero. It would settle down to about .5-.9 psi. I sent it back to Autometer and they sent me a new one, a few months later this one did the same thing. I sent it back again and this time I just sold the new gauge and bought a digital one. I like my digital, because it has peak memory, so I can see the max boost at any given time. It is a SPA Design dual gauge with boost on top and fuel pressure on bottom.

 

I had the same thing happen to me twice with my defi d. I am now on my third gauge. I have a brand new one and I am keeping it as a spare since just in case the one I am using does the same thing, cause the defi d has been discontinued.