I use it and only partially agree with what Scotie said.
I have about 90 pieces of 27" curves which I have always used - until last year when I entered the tin-plate world, which now limits me to using just my 42, 54, and 72 inch curves. There are still some uses for it on certain layouts. Not everyone runs the big stuff. I had 9 Railking PS2 engines ranging from steamers, small switchers, up to RS-3s and they ALL easily handled 27" curves.
- walt