He is promising, but he is not an import. How are the candidates doing so far this season? Let's take a look:

Yu Darvish: 44.1 IP, 2.84 ERA, 1.42 WHIP, 51 K
Hisashi Iwakuma: 8 IP, 6.75 ERA, 1.13 WHIP, 9 K
Wei-Yin Chen: 44 IP, 2.45 ERA, 1.20 WHIP, 32 K
Norichika Aoki: 51 AB, .255 AVG, .321 OBP, .373 SLG, 6 SO
Yoenis Cespedes: 106 AB, .245 AVG, .319 OBP, .434 SLG, 29 SO

Updated stats for our candidates as of 6/4/12:

Yu Darvish: 67.1 IP, 3.34 ERA, 1.46 WHIP, 73 K
Hisashi Iwakuma: 16 IP, 5.16 ERA, 1.38 WHIP, 14 K
Wei-Yin Chen: 60 IP, 3.75 ERA, 1.33 WHIP, 47 K
Norichika Aoki: 106 AB, .283 AVG, .339 OBP, .415 SLG, 16 SO
Yoenis Cespedes: 123 AB, .244 AVG, .314 OBP, .423 SLG, 32 SO

Darvish will have the biggest impact on his team.

Updated stats for our candidates as of 7/4/12:

Yu Darvish: 102.2 IP, 3.59 ERA, 1.36 WHIP, 117 K
Hisashi Iwakuma: 35.1 IP, 4.84 ERA, 1.39 WHIP, 27 K
Wei-Yin Chen: 99 IP, 3.64 ERA, 1.24 WHIP, 73 K
Norichika Aoki: 217 AB, .300 AVG, .363 OBP, .442 SLG, 26 SO
Yoenis Cespedes: 189 AB, .270 AVG, .329 OBP, .481 SLG, 47 SO

Updated stats for our candidates as of 8/14/12:

Yu Darvish: 140.2 IP, 4.54 ERA, 1.46 WHIP, 162 K
Hisashi Iwakuma: 71.1 IP, 4.16 ERA, 1.37 WHIP, 58 K
Wei-Yin Chen: 146 IP, 3.70 ERA, 1.25 WHIP, 118 K
Norichika Aoki: 345 AB, .287 AVG, .352 OBP, .414 SLG, 39 SO
Yoenis Cespedes: 305 AB, .302 AVG, .363 OBP, .502 SLG, 71 SO

It has easily been Cespedes. I had a feeling Darvish was too hyped.

Cespedes is mine

I am not sure that Chen is the best, but he sure is putting together a great season. I have to give major props to Chen who was overshadowed by the likes of Darvish and Cespedes.

Here's an interesting comparison between Norichika Aoki and Yoenis Cespedes so far this year.
Cornell ILRSBS - A New Name For A New Attitude : Player Toss-Up: Cespedes vs. Aoki

Good find bohringer9! Thanks