I've been making concrete stepping stones this winter, for a large garden I'll start next spring. The stones are supposed to look like short planks of old weathered silvery, distressed look. I was able to achieve the color well with a charcoal dye in the concrete mix, but I wasn't getting a good, distressed grain-look by hand.
After purchasing these rollers, my stepping stones are turning out exactly how I envisioned. The roller 'grain' is fairly subtle, which looks very natural. The rollers are fairly heavy-duty, thick forms of rubber, so they'll last throughout the project. The instructions that came with the order gave me some good suggestions, as well. Overall...I'm very happy with these rollers, and I'd recommend them.