I am newly registered with the forum, but have been searching here for years.
I started with BLU cigs at first and immediately noticed the lack of performance. The charging pack seems more like a gimmick now. The refills were over priced for what they offer. I still do not believe the refills hold anywhere near what they advertise.
Then i graduated to Joye 510. Better performance there. Used that for a long while buying and mixing my own juice. The leaking and short battery life led me again to something better. This should be less of an issue with the new 510 tank mod series.
I was an early adopter of the Joye Ego series from the original to the ego-t. Stuck with that platform the longest, but got really tired of the performance of the atomizers. I would say these are the better of both worlds (size, performance, battery life) IMO.
A few months ago I changed over to a Vivi Nova tank using Ego twist batteries. Still i found those batteries lacking for uncompromised all day use and dropping performance after about 4 months.
And most recently I have moved to an Joye Evic. I swore I would never get a screwdriver size PV, but years of use, changing experience level, and striving for a better vape, I moved to the Evic. Not everyone's choice, but great for what I need. I changed stock battery tube to a 18350 battery tube for smaller profile. This is a great size for my needs and has passthrough (charging while vaping) capabilities.
IMO for portability and performance something the size of an ego twist or twister I would say would be the best of both worlds. There are many manufacturers in that category, but Kanger and Joye are 2 reliable manufacturers. I am sure others will suggest more options. Those are the 2 I have experience with. smaller ecigs with charging packs and 2 hour battery life seem to keep me living around the charger and e-liquid bottle too much for my comfort.