180/23c

I rated only 8 because I don't have enough experience. However I purchased it because the first DE razor I bought couldn't allow me to center the blade. This inconvenience caused me a couple of cuts.
After that I purchased the Merkur 23 C and I found it excellent. Litweight, handy...I feel proud of it and it allowed me to use happily a DE razor! When I put the blade into it is perfectly centered!

Pros : Simple to use and loved the grip. This is my first DE razor. I used a fusion cartridge before and I like the feel and control of this a lot better. Taking a bit to get used to the different technique needed to shave. A little more practice and I am sure I will never go back to the fusion again.

Cons: still learning a lot, so other than no ability to adjust anything, I like it a lot.

I have the slant 37c and this. I find this one to be much more smooth and is an every day shaver for me. I love it, using with the Astra SP blades, it's a great smooth experience.