The crimpers work just fine. They do have the ability to be adjusted but I found them to work just fine without any changes. These will be left on a boat for any usage for a quick wire job. Over time, I am sure they will rust but just about every tool I have does this. Put a little oil on them to aid in this.
These do NOT allow you to change the die. WIrefy sells a kit that comes with or you can buy separately. You may want to consider your needs as a compact kit or purchasing different crimpers. I have found myself needing an open barrel crimper but this need is very rare.
Overall I am happy with the crimper especially for the price point.
I wish I had know about your company earlier. People at the RV park ask me where I purchase these great items as they have not seen them before. Your name is out and I hope you get many more satisfied customers. My rating is 10 out of 10 for product development and customer satisfaction. Thank Bill