We have ALL been through this and been subjected to the arguments of what is harsh, what isn't harsh and even the idea that no bit at all is the very best way to go.
First things first. A horse weighs 8x-10x what YOU weigh. When trained they listen very well to halts and half halts with that little piece of metal in their mouths. There are many who say that God put a gap between the incisors and molars on a horse JUST SO that we could control them with that piece of metal. People for 5,000 years all over the world have controlled their horses with metal bits.
For MOST horses we start them in a simple, jointed snaffle and many people will ride their horse his entire life in a simple, jointed snaffle. Many people refine their communication with their horse with a plain, mullen or low port curb bit. There are cases where a horse is more comfortable with a port in the mouthpiece and many bit manufacturers produce snaffle bits with a solid piece with a port that creates "tongue relief."
You should tt your instructor or trainer about what bit you should use. Many times a horse will toss his head or not listen to the bit bc of disobedience instead of pain. Many times a horse just needs more training or, if young, needs to have a softer training touch so that he can relax. THAT describes my 7yo QH. He was tossing his head and pulling on the snaffle at first. After I did ground training with him and established control he was quiet, with the same bit.
I cannot ascertain this for you bc I'm not there.
Here is an excellent thread to help you. =D Bit Information (Snaffle and English-Type Bits)