If you want a good and inexpensive toothbrush, go for Equate. A pack of two toothbrushes nicely packaged in a plastic case costs under $2. I have tried different brands, including Colgate and Reach, and I can say that Equate's version is just as good. The toothbrush has a slightly curved head that helps to reach farther into the mouth; the bristles are different length, which helps to better brush around and between teeth. The non-slip rubber handle provides a good hold on the brush. These are the same features you will find with more expensive brands.
My gums are rather sensitive, so I always buy soft toothbrushes; Equate toothbrushes do come in Soft and work very well for me. They are also durable and long lasting. I tend to apply a lot of pressure when brushing, and I have broken a couple of plastic toothbrushes, but it has never happened to an Equate toothbrush.