They've got 10 people watching those monitors though, you've only got 2 eyes and there supposed to on the road not the gauge
F1 engines are a little different to ours. F1 engines are pushed past there limits and then taken back a degree so there completely on the edge.
99% of people cant afford to run that sort of a risk with their engines, so are far with alot more accetable limit.
Im not saying gauges are a bad thing, far from it. But if people spent the 100's of sometimes 1000's they spent on their guages on the engine being built to an even higher workmanship standard they alot of the guages wouldnt be needed
Once again all IMO