New HPX170 owner here. Need recommendations on selecting a zoom controller that will work at a "crawl" speed. On-board zoom, much to disappointment, is not slow enough as compared to my old DVC30 which was about perfect.

There is no controller that will override the set zoom speeds set in the camera. That's been one of the complaints ever since the HVX200, that the slowest zoom speed available is too fast.

The only way you can get "crawl" speed is to do it manually, and easiest to achieve with aftermarket mechanical lens controller hardware (rail mounted) such as from Zacuto or Chroziel.

I used my Varizoom Stealth Controller on my HPX170 ... and if I apply a very light pressure on the zoom button, I can get a very slow zoom speed. Takes some practice - but, it works.