Hi there,
I live in Saigon, VN; so I put my 2 cts there.
I travel a lot inside and outside VN. Since I vape, I've made 1 round trip inside VN and 1 outside (to Malaysia) and I never had any sort of issues with security check at the airports.
For my domestic trip, I didn't have checked luggage, only a big hand luggage. I had 4 or 5 e-juice bottles (10ml) in a box inside the bag, 2 ego twist batteries with USB charger and 2 protanks and I did pass all the security check without problem.
For the trip to Malaysia, I put the juice, charger and spare battery in my checked luggage and only kept with me an ego twist with a protank to vape during the trip. And, once again, not a single problem. I always put the e-cig in my hand luggage for the x-ray. I put it among the computer accessories (mouse, adapter, cables...). Not sure if it helps, but...
Regarding the shops in Saigon, the only decent one I know is the one already mentioned in this thread:
Thu?c lá ?i?n t? | Cai thu?c lá
It is a small shop with very limited offer but the people here are nice and friendly. What you can see on thier website is basically what they have in stock. For the juices, they only have some Hangsen in various flavors and nicotine levels. The best is to go to the shop and see by yourself. I'm quite sure anyone would find a few flavors in the good nicotine level.
I tried this one:
Hirashop yesterday. They have 2 locations. The one on Ly Thai To street have almost nothing (just a few cartridges) and the one in District 4 is not a shop. They have a few items in a stincky backroom of a coffee shop! Not worth to go there!
As one can see, Vietnam is not yet a paradise for the e-cigs addicts. If anyone knows another good place to find the stuff we need, I'm highly interested.