I am getting more into mtn. biking now, but am still pretty new. More trips and stuff. Right now i have this old schwin mesa that is several years old. Its okay, but i want a new one. Can you get a good bike for 150-350?

Are there any manufactures that are better than others, or any brands that you definately want to avoid(poor workmanship, low quality parts, etc). I dont want to see some nice full suspension bike that looks great from some company that turns out to be really crappy.