I am debating if buying new 100hp injectors or just the tips.

There is a difference between $ 400/$600 depending on brand, that is A LOT.

So, why not just replace my tips with new ones, is it a difficult operation ( I mean is there anything inside injector that can be damaged) ?

 

its EASY! all you have to do is put it back together right. theres a detailed thread on here with pics and everything if your on still on the fence.