Which concentrate pen to buy???

[Stringer]

I need to buy a good quality concentrate pen that works with a preloaded cartridge that is threaded 510. Must be 510 compatible, no useless communist chinese 601 threads or anything similarly stupid. Also needs to work with other forms of concentrate. What should I get? Thanks.

 

[momofthegoons]

no useless communist chinese 601 threads or anything similarly stupid.

Really? Nice to see you haven't lost your attitude....