Playing characteristics depend on many variables, so I hesitate to comment directly. I also do not know what type sax (sop, alto, tenor, bari, etc) you are playing. So I would recommend going to a blog site like Cafe Saxophone or Sax on the Web and search these sites for the mouthpiece you are interested in, and study the comments that are related specifically to the type of horn you play.
Opps sorry I left out that info. I'm currently playing an Yamaha YAS 62 mk3 alto sax with a Woodstone reed(2 1/2). I read online that the Rico Graftonite mpc comes in 3 tone chambers, A/B/C/ ? What are the differences between them?
Here is a link to a chart for the Graftonite mouthpieces. A chamber is largest, C is smallest. Chamber size will affect the tone. A will be darkest, C will be brightest, B is intermediate. http://www.doctorsax.biz/musical%20instruments/mouthpieces/graftonite.htm
Note all of the Graftonite tip openings are larger than the opening on your 4C. This may mean that you should move to a softer read, but you will have to determine that yourself.