I have a handful of different devices (plume veil v1 and 1.5 clones, a big dripper clone, Orchid v4 clone, tohb 2.5 clone, infinite clt v1, zenith v2 clone). I like my tohb 2.5 clone best for on the go vaping because I can easily remove the top cap leaving the barrel on the deck and can drip directly onto my coils allowing the barrel to help prevent making a mess if I over drip. I also love how it vapes, and while some of my other devices may be more convenient for on the go vaping, they end up staying home because I dislike the vape quality they provide or because of leaking issues. I personally like to be able to drip directly onto my coils, I don't like when e juice gets stuck in the drip tip and ends up in my mouth. I also dread getting dry hits so I feel like dripping directly onto the coils helps ensure having a saturated wick at the coil reducing the possibility for dry hits (just my personal preference as I am a bit phobic about dry hits).
The big dripper is very good, great vape quality like my rdas with the convenience of having a tank attached. However, I have, on several occasions, accidentally had the drip tip get pushed in while in my pocket (pushing in the drip tip squirts juice onto the wick) and then it will leak into my pocket. It's really not too easy to fill, and the deck design makes it tricky to build on. These issues have caused me to not use it too regularly. I will say, once you get a build in it and get it filled up, it functions perfectly. It's quite a brilliant little device imo, it just needs a bit of refining. If the deck were redesigned to be easier to build on, it had a filling screw somewhere or some other feature to make filling easier, and somehow you could lock the drip tip in place or some other form of accidental dripping protection to prevent it from filling your pocket with e juice, I probably wouldn't use any other device.
I find my Orchid v4 clone has a good vape if I luckily manage to wick it perfectly, but i have not found a method of getting the wicking right everytime and often get dry hits (again, I hate dry hits with a passion), therefore it gets minimal use.
The plume veil clones I have leak quite a bit due to the airflow holes that go through the negative posts, I still use them pretty often, but only at home when a bit of leaking is not a major problem to deal with.
I love my zenith v2 clone, I use it on the go quite frequently just because it has become my favorite atomizer, however, I don't find it as convenient for on the go vaping as my tohb 2.5 because the top cap threads onto the barrel to lock the afc ring in place making its removal less than convenient, therefore I just remove the whole barrel to drip. The juice well on the deck is pretty shallow as well which makes for the possibility of a mess if you over drip.
The clt v1 mostly collects dust as I don't like the vape quality (flavor output is poor in my experience).
Several of these devices were purchased specifically with on the go vaping in mind (big dripper, Orchid, tohb). I keep going back to the tohb for on the go convenience, and the vape quality is fantastic. I just make sure to vape the juice level down before I put it in my pocket to prevent juice from leaking from the airflow slots when it's in my pocket. Sorry about it being such a long post, but I wanted be thorough in explaining my experiences because on the go convenience has always been an important feature for me.
