[DeTomaso] ANSWERS - Any experience with rivnut, nutsert, rivet nut tools

[Ken Green]

Thank you to everyone who provided information.  
 
Based on descriptions of the different tools, some are wimps and some are tough.  A lot are rated for the size (up to 3/8 inch) and material (steel or aluminum) of the nuts they can set. 
 
The most common higher quality tools are Marson and kits are sold for between $60 and $120 depending on the seller and the mandrels that come with the kit.  Each thread requires a corresponding mandrel, and buying more is around $15 each.  
 
Then it gets confusing because some of the Marson tools are described as up to 1/4 inch, and others that look the same are up to 5/16 inch.  It's not clear what the difference is.  McMaster Carr has a large selection, many looking like the Marson tool, but at a wide range of prices and ratings.
 
I am assuming that you can use any nut with any tool that has a mandrel with the correct thread.  There seem to be a range of nuts (see McMaster Carr), so it may be worth looking if you have a special application.
 
Ken