Slayer is fun, but lacking in xrd (in my opinion). He requires good reads, and requires some balls to play well. He has some bad match ups, and comes off a bit too honest when compared to the other bullshit in the game.
Yeah- with Slayer it seems like you have to squeeze every bit of blood from the stone (the general system mechanics) to have success with him against high level players (kind of like Pot, I guess?). I feel like you can still have some success with him pretty easily at lower levels of play with scrubby stuff though- mash that 6P, haha.