i own the Crown and two Starre Pros...
first off, there are no kanthal coils for the Crown, there is one ni200 coil available and the rest are stainless steel...
The Starre Pro has two different ni200 coils available and can also use every other Freemax Starre coil along with any Atlantis/Trton style coil...
the difference in performance between the two is barely worth noting, both produce stunning flavor and respectable clouds. the Crown has slightly better airflow unless you open up the tip on the Starre Pro, which does hinder flavor. as far as juice consumption goes, the Starre Pro is a guzzler with the ni200 coils, haven't tried it with the kanthal coils. th Crown is a not quite as bad with the ni200 coils, but guzzles like crazy with the .25 ohm ss coils.
fit and finish on the Starre Pro is good, fit and finish on the Crown is flat out excellent.
the Crown is extrememly user friendly, it's easy to fill, easy to break down, and easy to clean. the Starre Pro is a real bear, if you don't fill it correctly, you will loose all of you juice through the airflow. there is a vent hole in the top cap and you turn the collar that the drip tip sets it to open or close it. the cap is marked with an arrow and the on/off positions. basically, to fill, you gotta close the airflow, take off the top cap, fill, and (here is the part you gotta remember) when you go to screw the cap back on, make sure the vent hole is open/in the on position, as soon as you've screwed the cap completely on, switch the vent hole to the off position... this should take care of any leaking issues... the Starre only breaks down to a point, the chimney section and top cap/air vent control cannot be taken apart making them a little harder to clean...the Crown never leaks unless it's incredibly hot and outside, it's in you pocket, and the juice thins way out...
sorry for the long post, just wanted to give my opinions on what are, IMHO, the two best sub ohm tanks there are... i've owned the Zephyrus, Subtank Mini, SMOK TCT and VCT A1, and the Atlantis V1 for comparison...
oh yeah, you can put any 510 drip tip on the Crown, if you wanna use a different tip on the Starre Pro, it's going to have to be a log stem one to block off the airflow holes...