That’s a very loaded question, and it’s tough to answer.
This is because both materials have definite advantages and disadvantages.
If you want a very smooth shave, look for a carbon blade.
Carbon steel is harsh but also brittle.
This means that although it can hold a very, very sharp edge, it also takes a lot of work to maintain that lead.
Stainless steel is not that sharp, but it is much, much more difficult.
So if the proximity to shaving is the most important thing, then carbon is the best.
If convenience is your biggest concern, stainless steel is better.