Oster is definitely a good, stable brand. It's definitely a good idea, if you can do it, to spend a little extra for quality items; they'll perform better and last longer. My blender is a Ninja. I love it, except for having to clean it.
My favourite kitchen item of late has definitely been the air fryer, though. It does everything! French fries, pizza, chicken, salmon, french fries (the boy's favourite) and whatever else I don't want to cook. A big help, that one!