Mechanical or Electronic Gauges

I'm thinking of adding a supplemental oil and temp gauge to the Duster to get a better comfort level with the engine monitoring over the Rallye Dash units. I'm curious which type aftermarket guage set is preferred. Can someone give me some advice on purchasing these and the pluses and minuses of each version. I'm leaning towards electronic, but thought I should ask for more info first. Thanks ABody Guys...