Many people suggest using RC paper for contact prints if they're for making contact sheets of rollfilm negatives, for general perusal and such. But for finished prints I'd suggest going with fiber-based paper. It doesn't take any more room, just a bit longer washing time, but the results are much better. If you like Kertesz's prints, fiber paper is going to look closer to what he printed with. I'd recommend any of the eastern-European brands for a good start. I like the look of glossy fiber paper. A bit of selenium toning can add that special look.
Good luck and hope to see your results.
What kind of differences could be expected from fiber based as opposed to RC?