Performance wise I think they are very competitive. In fact I doubt you could tell a difference. However, in terms of ease of use the VPI 17 is by far the easiest to use. I have the 16.5, which is VPI's manual version of the 17. I still find it easier than the Nitty Gritty. The only drawback to the VPI is they do take up more space. Lastly is the Keith Monks--no longer in business, but every now and then you see a used one. This is the best performance wise, but will likely cost you considerably more than the VPI or Nitty Gritty.
