Depends on what you're looking for I guess but for me,
Mods: Lost Vape
Stock Coil Tanks: Uwell
RDA's/RTA's/RDTA's: Steam Crave/Vaperz Cloud
Mech Mods: Purge
Pod Systems: Geekvape?
I love DNA devices and (for my vaping needs) my Lost Vape Paranormal and Drone both work wonders whether I'm dripping or squonking. I personally don't use stock coil systems too often but I was rather impressed with the flavor and output of the Valyrian 2 and the new Valyrian 3 (especially their single coils). Steam Crave is the main company I use for RDTA's, just nothing can beat them imo, and Vaperz Cloud has both of my go-to RDA's (The Asgard and Valhalla). For Mechs really almost any company that makes any solid mech mod could be here but I own mostly Purge mods so I guess I have to put them here, and finally pod mods and pod systems. I do not personally use pods, I like big clouds and devices which push a lot of power, but I have seen a lot of solid pod mods and pod devices come out of Geekvape recently, and customers seem to be of the same opinion at my shop so I have to give them credit where credit is due!