I hate pinked edges - they never want to line up and you always have to check if you were sewing in the valey or peak.
I only use them for rag quilts, since this method is forgiving minimal precision required
Tazz - thanks for the tip - I think it was on Fons and Porter that someone sent in to use several layers of aluminum to freshen up dull blades by cutting through several times. Tried it the other day and it didn't work for me. I didn't have any luck with the rotary blade sharpener either so a cheaper blade that actually works it trully a blessing.
You do need to have the correct blade size for your cutters as the cutters come in different sizes. One of the ladies in our quilt group in USA had been using carpet blades bought from Fronteir Freight 4 for $2.00. They also come in different sizes. Several of us tried these in our Olfa cutter and they are great and the price is great. I could not see any difference compared to the ones sold at leading fabric stores at a much much higher price. The blades were the exact same size and all stamped made in China from both stores. Check it out. I had purchased a sharpener years ago at a sewing store and have no problem sharpening my blades. A very good purchase to make as it saves from purchasing more blades.
The group I quilt with makes "passage" quilts and they are usually 48" x 60" finished. Call the group you want to donate to and ask what their preference is - do they want finished quilts or just tops - some groups in our area have longarm machines and they quilt the tops themselves. When I donate to them, I provide a finished top and back and they provide the batting.
Donated quilts - I make scrap quilts for donations and have used the following calculations for years! Find the total square inches for the quilt and multiply that by .06 for value of donation - have agency give you a signed receipt and I always take a picture of it to staple to it. I have been doing this for too many years and the IRS has never come to get me for it. No promises - can't even remember how I came up with the formula, just that it has never changed over the years.