Rode NTK with what Preamp? or without Preamp?

I am going to start explaining my situation, bare with me =] . Sorry and Thanks in advance

I currently ordered (Don't have it yet) a Rode NTK mic which is going to go directly into a Presonus Firebox.
Right now I have the Behringer C-3 Mic and it doesn't seen to get enough gain through the Firebox

Now from what i heard, some people say a preamp is recommended (some people says also not enough gain), some people say it's not (for them, they say its perfect). And for the people that says a preamp is needed, they always suggest products that are waaayyyy out of my budget (8-ch). I am just doing simple VOCAL recordings at home for fun =]. And MAYBE sometimes have a friend over to play the guitar.

So for you people out there, what should I do? Just go without a preamp or
please suggest a $100~250 one that is good with the Rode NTK or even the Behringer lol.

and also 1ch or 2ch?