I purchased a V2 pro Series 3 vaporizer and immediately encountered an issue with the e-liquid cartridge. A defect in the cartridge caused the outer ring/collar to come unsecured and stuck in the vaporizer itself, preventing me from being able to switch back and forth with the loose-leaf cartridge I had bought at the same time. I wrote to the company and was treated horribly - without any investigation V2 pro declared that the cartridge had simply reached the end of it's life cycle and it was time to replace. I was shocked. It had been less than 30 days (only about 20 days since receiving the device), I had filled it only once, and encountered the issue immediately. Numerous emails over the next ten days have left me completely without trust or respect for this company. They immediately laid on the excuses and tried to deflect their responsibility in the matter. There was no attempt to resolve the issue. Their customer service is so lacking that I would suggest no one uses the product - it is not worth the frustration of having to address what should have been quite a simple warranty issue. I've read of a possible class action suit against this company and would certainly support this approach. V2 Pro should be shut-down if they can't even provide the minimum level of customer support and respect towards it's clients.