Haven't paddled the new Mamba. Have a stomper. Took me a little bit to figure out where I like the seat, but once I got that dialed in I found the boat very responsive. Resurfaces well, tracks well and rewards you when staying in a proactive position. Overall I really enjoy the boat. The outfitting is stellar.
My good buddy just got the new Mamba and swears it's the best thing since sliced bread! Don't think you could go wrong either way! Have fun!