I have never used or seen one myself. I think a few YouTube videos are available giving demonstrations. Criticisms have been that the slaphammer is of low quality, but the spot welder works good.
Customer reviews gave it a 4.8 out of 5 stars and all 5 responders said they'd recommend it to a friend. I also considered buying one but the timing is not right for me since I won't need it for another few months.
