Dead Space 2 questions

I bought the game two days ago and I was wondering if you guys would share some of your foresight with me.

Right now I have the plasma cutter, line gun, and pulse rifle. What is your take on the javelin launcher? looks like it would be ineffective to me, same with the flamethrower and buzz saw.
The force gun was one of my favs in #1, how is it here?
I'm focusing on upgrading my plasma cutter and pulse gun, any other wepons you highly recomend useing?

Flamethrower - For lulz only, or to use against bosses at times. Its great for Swarmers (those little things that dies in single shot from any weapon since you can burn them at once).

Javelin - Its pretty effective, but watch out when you use the secondary electricity, it actually consumes one more ammo, I made the mistakes early on when trying to electrify enemies with 0 ammo and it forced me to reload.

Force Gun - Secondary fire changed to one single CHARGED beam that is narrow and its like Contact Beam.

I had these four weapons when the ending credit rolled
Plasma Cutter
Pulse Rifle
Line Gun
Contact Beam

I really like the force gun. Plus i get ammo all the time so its rather usefull