I remember Ashley stating that particles are essentially just sprites with bullet bahivor (can´t remember exactly but something like that), so there is basically not much difference in performance between creating particles with the particle object or creating particles with "create object". The benefits are that you can apply physics behavior or other stuff aswell that the particle object does not allow. So apart from the additional impact (performance wise) from the bullet behavior or the physics behavior there is no difference. 250 particles are likely to be way too much though, especially with physics, you probably should do 50ish maximum. But you can try the bullet behavior, I think it has less impact on performance.
[quote:2sw8uhjo]tons of event sheets.
Why would you need tons of event sheets for this?
On enemy hit | Create object "foo" at position XY
Repeat 20 times |"foo" Set bullet angle to rand(A, B)