[NO_H2O]

Well I have read that before. It is a nice sales pitch for the dipstick they sell. In fact I have one but i wired it to triger its own light. The idea of turning on the oil press light and makeing stop to think, Is it no oil pressure or just hot? doesn't sit right with me. You might think it is hot and do nothing for a few seconds while you think. Then the noises you hear while your engine self-destucts will let you know the it was no oil pressure and not high oil temp and You were wrong,,,,,thanks for playing "BERG-Dipstick Roulette"

There are a few places to mount a sender for CHT. The spark plug is the best place to sample the temp, the other type senders will give a much lower reading. This is why they are picking on the CHT guage. The same can be said for the oil temp. senders. you can sample oil temp in alot of places, some will read hotter than others and some will read the temp of stagnet oil(useing a "T" at the press sender).
That whole dissertation on guages is there to sell a product, some of it is true. But if you select the proper guage, sender and location you will have a good idea of what is happening in your engine and can see a trend before a light comes on to tell you that you now have a real problem.
Remember, even if the guage is a little inaccurate, it still gives you a referance and when you have a change in the referance you know that something has happened and you should take action or monitor the changes. The more information you have the more you know about your engines operation/heath.