man, dont you play Gran Turismo???
2 way, has the limited slip on both acceleration and decceleration, 1.5 is mostly on accel and only partly on decceleration. there is also a 1 way, which is only on acceleration.
the advantages on each depend one what kind of driving, and what kind of drivetrain you has (FWD or RWD or AWD).
Basically since this site is for hondas, then ill just say it for FWD.
1 way is good on drags and stuff cause you only need the accelaration part
1.5 is good i guess for FWD on road courses and AutoX and stuff cause you have the full limited slip on accel, but only part on deccel. tis is good for FWD because they are already hard to turn on sharp turns. The more the wheels are spinning at the same rate, the harder it is to turn. With the 1.5, you basically get both wheels powered on accel, but when you slow down for a turn the wheels aren't still going at the same rate, which makes the turn easier.
2 way is a pain in the ass for FWD because when you decelerate, both wheels are still being powered so when you make a turn, there is tire slippage to compensate for that. Basically when both wheels are powered, your cars turning radius is bigger, and when you make a sharp turn, the tire spin because you are turning in a sharper circle than what the car is capable of.
If I am wrong anywhere on here, correct me