I started with the Blu, went to the Halo G6, stepped into a VV Triton and went crazy afterwards.
Some positive thoughts; Halo gear is very nice, no frills, no BS gear. Their juices are really solid in their gear as well. The VV Triton really made me decide to continue vaping as a hobby and lifestyle. Their CS was extremely impressive. I like the fact that it is a down home US company. I have turned a few friends on to Halo gear (thus far all have graduated to or started with the Triton system), and all have been very happy with their purchases.
Some negative thoughts; In many instances it is hard to find a local retailer. Their equipment is all proprietary. It is not a huge deal, as you can buy $3 adapters to convert it to most other devices, but still it is a bit of a qualm of mine. If you like to tinker, you will find doing so on their specific gear nearly impossible. Again, you can buy adapters and do some building on other platforms, but it is worth mentioning.
I can honestly say that thanks to Halo I have been stinky free for nearly 3 months, I have a new hobby, and a healthier lifestyle. But I have since sold off all my Halo gear as I have taken to mechanicals and rebuilding my own attys.