I see nothing wrong with having an oil sensor monitoring the oil level. It's a good, extra security feature, especially for those who don't check their oil level regularly (and that's probably most people). But getting rid of the dipstick completely is just a really bad decision IMO. Electronics can and do fail. Dipsticks don't. My '96 has both a dipstick and an oil level sensor which I think is the best way to do it. However, the oil sensor has given me false warnings before, highlighting the need for a good old dipstick.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL