Just some thoughts I'd share on this topic.
1) Evolv doesn't have a patent covering all forms of VW, rather it has specific forms of VW implementation as described by the claims of their patent.
2) To infringe said claims, a competitor must perform each and every element of said claims. Thus, for example, to infringe claim 1 of their '330 patent, an electronic vaporizer device must include, in part: a power manager operatively connected to the user input device and the power source and configured to regulate the power level delivered to the heating element to substantially the wattage setting during activation of the electronic vaporizer device,
regardless of heating element parameters and a state of the power source, to consistently control a quantity and a quality of vapor produced by the electronic vaporizer device. (Emphasis Added).
3) Under patent law, claims must be given their broadest reasonable interpretation. Accordingly, the language I bolded above will probably make or break the case for Evolv. The reason is that the defendant will likely claim that the refusal to fire when an atomizer's resistance or battery voltage is outside permissible ranges means that their mod's do not have a power manager the performs what the bolded language above requires.
4) Patent claims when litigated go through what is called a Markman hearing, where parties can propose how various terms or phrases (e.g., the bolded language above) should be construed so that the jury can understand them. The judge than issues a Markman ruling giving the claim constructions, which may accept some proposed constructions, reject others, or reach different constructions than what both parties wanted. Regardless, that ruling is typically what often decides cases. Personally, I think this aspect will be an uphill struggle for Evolv, but I'll keep my legal opinions to those who pay me for them.
5) Evolv has ongoing prosecution based on the original patent filing. This isn't all that unusual, as once a patent examiner provides notice of allowance, an applicant often takes what it has received and than files a continuation application trying to get better claims. Accordingly, Evolv may some day have patents issued that could have more commercial impact, but since they didn't expedite prosecution on their continuation they can only sue on the one patent they have now.
6) Patent enforcement is limited solely to where a patent is granted. While patent treaties facilitate the filing of patent applications internationally, a patent granted in a country can only apply to products and services within that country. Accordingly, Evolv's U.S. patent only covers the U.S. market and has zero influence over what goes on in Europe or China. To affect those markets, they would need patents granted in those areas.