also if you've ever had an oil pan off you'll notice there's a hole in the baffle the dipstick needs to go through, I've fixed a couple of these. usually the big sign this needs done is that your dipstick doesn't want to stay in or pops loose or whatever.. just bend the tip a little so its as straight as can be and usually it'll slide right in that hole in the baffle.
but yes i too have noticed several different dipsticks.