Ninja Flex with the “J” Style Hot end

Has anyone used Ninja Flex or similar filament on the old “J” Style hot end successfully, if so how difficult is it to get it printing decent?

 

Shouldn't be any different than an all metal. A guide tube between the hobbed bolt and hot end will help.

 

I had bought some mm i. d. ptfe tubing already to bridge that gap( ive had the filament buckle over there quite a few times) but it doesn't fit through the feed hole in the carriage. all i've been able to do is cut a small piece and taper one end to snug it in. but i have to replace pretty often. I've thought about drilling out the hole so the tubing would fit through but didn't really want to take the rick if its not necessary.
do you know of a way to make it work?

 

Drill baby drill.