They are ok, but they sound a bit odd to my American ears. I will say what I would use instead if I were to be reacting to a funny situation. 1. We don't ever see such things. 1. We never see such things 2. We don't see things like that very often 2. You don't see that every day! (said ironically) 3. Such things as these are seldom seen (said very ironically).