I discovered Mig Vapor when I learned V2 had gone out of business. MIG was the only vape site I found that offered interchangeable parts for V2's e-cigs and vape pens. A US company, they also design their own vaping hardware.
One of the newest, most advanced refillable all-in-one vape pod pen is the CT1. Designed by Next Mind, this ultra portable mini vaporizer has features never before offered an open-system vape pod device.