There is a marvelous 1/4 inch foot that is clear plastic and is also marked with 1/4 inch horizontally at the needle position as well as 1/4 inch behind the needle and 1/4 inch in front of it. (Is that clear as mud? )

It's made by Littlefoot and available at some LQS as well as at http://littlefoot.com. I got one this summer and LOVE it.

I found I don't have to worry about the scant 1/4" if I use very thin thread. When using size 60 or or lower thread I adjust my foot guide a fraction to compensate. I don't move my needle. If I stay true to the seam allowance the blocks will match no matter if I use a scant or full. That's hard to do without some sort of guide.

Alright call me a rebel, but unless triangles or exact pattern, 1/4 is for the birds (my opinion) and no this isn't to offend, as long as all the seams are straight and the same measurement, I go for something that can be seen normally lands closer to 3/8, don't have to worry about fraying, just gives a little extra room to work with if adjustments need to be made. :)

you could always put it into your cutting and then just sew a standard 1/4 inch.

if the pattern says to cut 2.5 inches just cut 2.5 plus 2 threads more of the fabric.

You got THAT right! I agree. When I use 1/4" or worse, scant 1/4" it always gives me trouble. First washing and it comes apart....and you really can't fix it because it has frayed some and now it is too small to come together correctly. Now I compensate for that by doing some stay-stitching ( don't have a serger) on the seams that look like they may come apart easily. And am seriously considering a larger seam allowance on my next quilt. (Hope I remember ) lol

Just have to cut larger enough to make up that difference if doing points and triangles.

Nothing works for everybody. Learn your machine. Spend a whole day figuring it out. You are in control. The tool works for you. Once you figure it out, you work together. peace.

I use my 1/4" foot and slip the needle over to the right one click - it becomes a scant 1/4"

I never thought about moving the needle over a little bit. That's a good idea. I will have to look into that!

What kind of machine do you have? I found out from my Bernina serviceperson that the needle can be realligned! (I have a 30 year old 830 and just learned that recently!)