I have LOTS of rulers and it depends on how many quilts you do annually. Do a little research - some rulers do double duty. Some are unnecessary - just do a little more work on your part. I wouldn't buy special rulers if I was just making baby quilts, but a specialty ruler for a full or queen sized quilt can make a huge difference in your frustration level. That said, I personally avoid rulers that have only black lines as I can't see them on darkish fabric, which is most of my stash.
I guess, give some examples of patterns requiring special rulers? I'm sure posters can tell you what will work and then you can decide when to get one and when not to.
For instance, I love, love, love Eleanor Burns' Flying geese rulers. However, you are limited to only 4 sizes. Is it absolutely necessary? Nope. Since those rulers came out, there are other ways to make Flying Geese that don't require her rulers, although I wouldn't be surprised to find that this method was actually based on her method. I keep mine and recommend them, but if you don't have the $$ or space, not necessary.
Last edited by IAmCatOwned; 05-02-2012 at 03:14 PM.