"Best" way to make rounded (concave and convex) corners?

[Hirohito]

I'm making my first (of many) "testing" maps, where I figure out how to make gameplay work, in addition to getting the hang of the tools. I wanna get used to making rounded corners, but I'm not in the mood to test each method and see how much of a drain it is on compiling and framerate. I tried making one out of cylinders (http://www.halflifestorm.com/?page=t...ls&tutorial=19), but vbsp spewed errors when I tried it.

My question is; what method of making rounded corners is the least drain on framerates and compiling?

~ fixed that link for ya