While I was working on the Zip Pocket Pouches pattern these self-cover button parts arrived it the mail. I originally mentioned them here, and after receiving and using them I definitely recommend this style of self-cover button.
I already had the cover button tool for putting them together, so I immediately whipped up a few to try them out. For the 7/8" ones above I used a scrap of fabric that was interfaced. For the smaller ones below (5/8") the interfaced fabric didn't work so well. They are just too small to deal with the extra layer. Using non-interfaced fabric was easier, but overall the smaller ones were slightly harder to make.
The wide shank is wonderful--much better than the skinny wire shank self-cover buttons. I still like those too, since being able to remove the wire shank to make them into magnets or tacks is also fun. But these wide shank ones are just really, really nice for making buttons. They are very stable and sit slightly lower than the other type.