I do kind of agree with you on having both, now that you mentioned it. Couldn't hurt. I've mostly had gauges and in 60 years of driving have learned to depend on them. The one occasion (and it was with this truck) when I only had an idiot light...it didn't come on. I had very low oil pressure and only noticed the problem with the change in engine sound. Luckily caught it in time and shut the engine off. It was close, but that was a few years ago and engine still behaves great.
