I made one quilt using the Quick Curves Ruler by Sew Kind of Wonderful - their site has lots of pics and info (as does IG, Pinterest etc). They have two patterns for Wedding Ring-type quilts, the Metro Hoop which is single rings and the Metro Rings which is double rings.
It was made using the flannel pjs my daughters wore which I saved since they were little. It turned out really well. The beauty is in being able to use scrappy fabric and the curves are gentler than other patterns so easier to sew together, if you're not that great with sewing curves. I use lots of circles in my quilts but still enjoyed using the QCR.
The other advantage of the QCR is you can use it for a bunch of different patterns, so you save $ by only buying one ruler rather than a bunch of different templates.
Good luck!