I installed the Dakota Digital VHX in my 1987 Diesel 3/4 4x4 Suburban last spring. I just turned 4,000 miles yesterday.
Very easy to wire up. Set up was a bit nerve racking, but once I figured out their language it got easier. I got the 4,000 rpm tachometer face to go with the 6.5. Something with their programming made it so I had to designate the engine as a 4 cylinder to get an accurate tach reading. But once that was figured out. Every thing has worked great.
I like it and every time I get into one of my M1009 trucks, I miss it. I would do it again if I were to build another truck. I was tempted by the new next step up gauges. I could care less about different back ground colors. However, having a reading such as temp, oil psi or fuel level turn to red like the NASCAR gauges would be neat. Not in my opinion $400 neat though.
Your own needs might be different.