Hey. They look good, okay!
Opinions are opinions, though artistically (and typographically) speaking the SMB3 letters are a mess. The letters are all capitals, yet they have a strange variety of sizes (especially the O and the Q). S has a duplicate, and there are also several other duplicates even though they're not on the right side. The thickness of the letters is heavily inconsistent, sometimes even within a letter, and the way some of them are drawn don't bring out good qualities in the letters, like the J. The shading is a mess, and coupled with the colors it makes the letters look like dirty play-dough.
Some of these problems lie in the way the original SMB3 letters were drawn, not just this sheet. So it's not really BmatSantos' fault that his came out looking a similar way.
Take a look at the SMW font now. It still has roughly the same cute, jagged look to the letters, but no parts are too thin or thick. All of them are of similar size. There are no duplicates! As well as that, all letters with similar properties (like P, R, and B) are drawn as a single shape with several variations. Notice that the SMW font still uses green, yellow/orange, red, and blue. However, these selections complement each other using greater contrast in hue and in brightness. They don't have shading either, but the lack of shading doesn't hurt the quality of the letters (meanwhile, the shading of the SMB3 letters do make them look worse because of their poor application).
Again, opinions are opinions, so if you have any good reasons that you like the SMB3 letters then I'd like to hear them. The SMB3 letters aren't inherently bad in my opinion, they just look bad as they are. With the right work done they could look even better than the SMW letters.