There is no reason not to buy a twin in principle.
Really?
Well, I can think of several SEP's who met their end in IMC/Night due to the failure of the single donkey.
Most recent?
VIDEO + FOTO: Ogledali in posneli smo kraj letalske nesre?e | Svet 24 na najdi.si novicah
Piper Arrow III IFR from Vienna to Ljubljana crashed 3 NM south of LJLJ after apparently loosing the engine during approach.
A twin would have made it home.
If you are flying IFR with low ceilings, over the sea or at night, you got the choice between a twin or a parashute equipped airplane if you want to survive an engine failure.