Today I tried a Personna red blade for the first time. So far, nothing has been as consistent as the Astra SP blade. The Feathers were good, but I didn't care for the Derbys.
The Personna started out just fine. They flowed down and across my face and seemed to be giving me a smooth, close shave. When I went for the 3rd pass ATG, I had some problems. The blade didn't feel as smooth on my neck, and when I got to the chin, the Personna just ran out of gas. My whiskers are a little tough in that area, but that's not out of the ordinary. The blade was really pulling, so I added more cream to try to help. After a couple of seconds, I could tell that this blade wasn't going to finish this shave without causing me some serious pain. I called in my other razor, which was still loaded with an Astra SP, and it just sailed right through the tough whiskers. I was really shocked at the difference!
It seems like a lot of people like the Personna red blades, but for me the Astra SP does a much better job! I guess blades really are a personal thing.