Just wanted to comment about the Newport butane and the fact that it is $15 a can. The "near zero impurites" means simply it is under 50ppm contaminants, I believe the industry standard is around 15ppm anyways, so this really doesn't mean anything, it is simply a marketing tactic and when you pay $15 a can, you're paying at LEAST$7.50 of that price on marketing alone. Based on the cost of similar butanes, it's probably a little more, if you really want the purest you can get, go for n-butane, or Xikar brand butane. Xikar's standard is 15ppm, but most high quality brands are in the similar range; Xikar also costs roughly the same as newport at $4.99/100ml.
Excerpt from Xikar's site: Each production run of our butane is analyzed and is accompanied with a certificate of analysis. All of our butane is A28 aerosol grade butane triple refined to eliminate water and contaminants. Some talk about 3x refined or 4x refined or even 5x refined. These marketing slogans don't indicate the actual quality of the butane. If the refinement process isn't high quality you could refine it 100x and it may not be "clean" butane.
If Newport did that, THEN it may be worth $15 a can, otherwise it's just about the same quality as any other brand, like Colibri that is allowed to use the "near zero impurites" brand...