Kayfun mini v3 for sure. Five isn't great for mtl. Chimney and air intake are too big unless you spend even more on the mtl kit.
CHeck out the by-KA v6.
@qorax just made a video or two on it if you want to see how it works. He does tutorial stuff not reviews. So if he's reviewing it he likes it. But he's tried most good flavor tanks and has videos. And while he is a restricted direct lung vaper his videos are very helpful to see the inner workings of authentic tanks.
The by-KA v6 is a custom built tank under a hundred bucks. You choose the airflow. Deck style. Tank and chimneys. So
You can have s bunch of possibilities but for you the
Nano kit with 2.4mm airflow deck and a tank
If your choice would be great. Inexpensive and most people seem to love hen.
If you cans spend a little more the gp heron v2 or spheroid v4 are amazing.
The spheroid is simple to build 16mm tank. 3 mm and it is a flavor monster.
Finally the most expensive is the cloudmods cloud one. It's more of a pain to buy. You have to go through Facebook. And wait for s list. And get on the list. But it's an amazing device.
You said you had a kayfun and we all
Assumed authentic I think. If it's a clone and our budget is lower let us know.
The goblin mini v3 with the single coil adapter should work well if the v2 is any indication. And there are a few others. But buying s nice boutique device is not as expensive as it seems given remake prices / certainly costs way less than buying s tank that takes coils and using it for any length of time.