With the stock b18c JDM tranny I hear they are only good up to 350WHP... is this true?

Who makes good aftermarket LSD tranny parts? I want to beef it up a little bit but it's also a daily driver. I need to be able to handle turbo eventually... 12PSI, hopefully 300WHP... I dont want to burn it out with the turbo. But, at the same time I need to drive this everyday.

Are there really any advantages in the LSD tranny? Any Horsepower loss?? I just basically need the 4-1-1 :fawk:

Thanks yall.