Lee Dae-Ho is a 31 (will turn 32 in the middle of next season) year old 1st baseman for the Orix Buffaloes. The 6'4 255 right-hander has turned out to be a very good hitter in the NPB after emerging as perhaps the most dominant hitter in the KBO. Lee is not a free agent and I believe he would have to be posted, and Orix has said that they are not planning on doing so, wanting to keep him.
In his last two seasons in the KBO (2010-2011), Lee lead the league in average both years, and was 1st in homers (his 44 homers in 2010 is 8th best all time, 6th best from a Korean native) and 2nd in homers. He was also top 10 in walks both years (though just like in the NPB, he struck out more than he walked).
Lee is most notable, in my opinion, because he is outhitting teammate Yoshio Itoi, the best Japanese position player prospect, by OPS this season. However, one of the reasons Itoi is attractive as a prospect is his secondary skills and Lee does not have these secondary skills. While I think he moves reasonably well defensively at first, he is not going to win any points with his body type.
The last player I can think of that came from the NPB to the MLB as a bat only player (meaning they didn't have baserunning or positional skills) is Hideki Matsui. Hideki Matsui was a horrible rated defender in the outfield when he came to the Yankees, though his reputation when he signed seemed to be that he held his own with decent range and fundamental play. But considering he was clearly signed because of his bat, it might be helpful to compare how the two players stack up statistically based on their respective NPB eras:
Matsui's last two seasons in the NPB:
127 BA +/139 OBP +/169 SLG +
130 BA +/147 OBP +/176 SLG +
Lee's two season's in the NPB:
113 BA+/118 OBP +/138 SLG +
118 BA+/116 OBP +/135 SLG +
So Lee isn't in the same class as Matsui but that is to be expected since Matsui made nearly the equivalent (based on 2013 salaries as interpreted by Baseball Reference) of nearly 8 million dollars in the first year with the Yankees. Lee is making the equivalent of about 2.5 million dollars this season with the Buffaloes. If you expect Lee to see a drop in OPS + of about 35 like Matsui did from the NPB to the Yankees, you are looking at a below league average hitter, which would profile as a bench bat/pinch hitter, not worth even matching his salary with Orix.
So I watched Lee in a series against the Rakuten Eagles, and kept the Yahoo data of his plate appearances in a spreadsheet and took notes on his at-bats as well. Since I was expecting four games of data and only got two, I found a video that included 24 of Lee Dae-Ho's 25 home runs from 2012 and charted them in the second tab (labelled "2012 homers"). This will give us a little bit better idea of what pitches he is hitting for power (classifications are just from what I thought the pitch looked like, so readers may want to watch the video themselves to make their own interpretations)
Masahiro Tanaka is the best pitcher in Japan for a reason, but he really fooled Lee with the splitter because he couldn't catch up to the fastball. It seemed all Lee could do was foul off the fastball, so he was having to speed his bat up. When he did, he whiffed horribly on a splitter, falling right into Tanaka's game.
Lee was also fooled really badly on a breaking ball, taking a big cut no where near where the ball was pitched.
I do like that he saw the best pitcher in the league and then the next day saw a lefty "junkballer" in Wataru Karashima. It gave a diverse look. I wish he would have faced Norimoto, a young but polished pitcher with middle of the rotation MLB stuff, but the game was rained out (which is why I have data from only 2 games, not the originally scheduled 4).
At times, Lee's swing just looked huge, really looking too long and slow, causing a horrible whiff on a high 92 MPH fastball up around the shoulders. Even slow high fastballs seem to tempt him.
His raw power showed up as he hit a ball out of the zone all the way to the warning track, but he was very prone to the infield fly-ball because his swing would get too much of an uppercut. Still, he showed good plate coverage, with the ability to reach balls on the outside part of the plate.
You can see those last two qualities especially in this swing of one of his homers from last season:
That is an 88 MPH fastball on the outside part of the plate, and Lee has the bat speed, strength, and plate coverage to pull it out of the ball park. I count only 3 homers to left-field by right-handed batters in the MLB this year on pitches low and away and at least 88 MPH (Scott Hairston, Jeff Keppinger, and Paul Konerko). That homer is a pretty impressive feat, and it was done in a season and a league where only 1.3 % of all plate appearances ended up as home runs.
As far as average wise, Lee has hit better against righties, but his home run percentage and BB/K are both better against lefties, so he has pretty normal platoon splits, not anything notable or concerning.
There are some really impressive at the plate skills in Lee's game, but it doesn't come without some question marks as described above. None of his 2012 home runs came off premium velocity, with none of them even coming off pitches at least 90 MPH. Good high fastballs could be a real problem for Lee, which makes it unlikely he would translate to the Major Leagues. Even assuming that Lee translates normally statistically (that is, the holes in his game would be exploited the same way percentage wise in the MLB as they will be in the NPB, a big reason I don't really use translations anymore is because baseball between leagues doesn't often work like that) he would still project to have less power than a league average MLB 1st baseman or DH. While he isn't one dimensional at the plate, I don't think that the average/OBP skills will play up enough to justify a MLB contract and posting fee to bet on his power. At the end of the day, it comes down to the secondary skills. It probably would be worth betting on a bat like Lee's if it also came with defense/positional value and speed.