I visited their website and I see they offer twisted nylon two ways, regular and heat set.
There is no shortage of companies who make regular twisted nylon. Heck there are two companies in Miami that make that. The problem is it is lousy rope. It is very soft and abrades easily. It really doesn't last as long as it should.
High quality rope made by Samson and New England is all heat set.
I suggest you spend the extra money and buy heat set rope.