Personally, I turn it on to be sure that I cover everything, but to be honest, I do not think that it is ever used. I wouldn’t worry about it if you don’t want it, but I try to be as cross-browser compatible as possible. You can also use something like Curvey Corners (google it), which (I think) just allows you to put border-radius and do the rest for you using JS, and also adds border radius support to browsers that don't support him. There are similar things for other CSS3 things, but this is really the only one I use.
I just can't wait for CSS3 to become widespread, so we can use it without worrying about all these useless prefixes.
JacobTheDev
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