After 5.4 came i decided to give my blood dk some attention.
However i noticed a bug about Soul Reaper - the spell's tooltip states it gives a 50% haste buff, but the actual buff's tooltip states it gives a 30% haste buff.
I was using the glyph of Swift Death (new in 5.4), so i do not know did that perhaps bug the haste buff's tooltip - but there definitely is a mismatch of information, cause there is a big difference between 50% haste and 30% haste :/