Hehehe...
The second I got my PT1, Kanger launched a PT2, which was a vast improvement over the PT1--it could be taken apart for cleaning, and all parts were replaceable, including the drip tip. I was in heaven for a couple of months until they launched an Aerotank with much better air control valve.

Then they started improving the AFC valve and the dual coils; there are three versions of the AFC valve and of dual coils as of now.
Looks like Eleaf is doing the same thing now--with their tanks and their batteries.
I did rebuild a few Kanger coils, but it's a PITA--for me. If I'm to rebuild anything, I'd rather rebuild a rebuildable, and have a couple of tanks with replaceable coils for convenience.
I'm still hoping that Eleaf will make a Lemo V2--20-22 mm, without that stupid skirt that hybrids on the Evic, with better AFC and fill method, perhaps top filled. That would be my dream RBA--well designed and user friendly. I don't sub-ohm, I don't want anything with a huge airflow. I'm not into exotic coil builds. Basically, I want a Kayfun-style RBA that will give me a bit more airflow options than the Kayfun does. Why nobody makes such a tank is beyond my comprehension.
So there. Rant over.
Carry on.