I've demoed and used a lot of e Pipes and I have to say for the most part they're crap. Not trying to knock anyone else that uses them but they're good only for very light vaping. They fall apart quite quickly. I actually did a review on the 601 a couple years back you can dig up on Youtube.
If you want something top notch have a look at these guys: http://www.epipemods.com/#
Their work is fantastic. (We have no affiliation with them.)