I was a bit sceptical at first since there wasn't too many reviews but I decided to give it a go.
The package arrived quickly and the roller came with a case, sealed in a paper container. The needles seem to be exactly 2,5. I sterilized the roller for 15 minutes before and after use. This is very important! It didn't hurt too much but I got a bit red and it felt stingy, like a sunburn. That is to be expected so I knew that the needles were sharp enough to penetrate the skin. The day after there was no redness and my skin appeared to be smoother and less textured. I will continue to use this roller :)