I’ve been using my dryer balls for over a year. I really like them, and I save money because I don’t buy fabric softener any more.
However, clothes and towels, in particular, are not as soft as when I used fabric softener. What it DOES do, it fluff your laundry so it dries faster (than without them). For me, the trade-off is worth it. If you like the scent softeners add to your clothes, you’ll miss that with these too. I don’t like extra fragrances, so it’s perfect for me.