I do not know about katana kit. But read some about it just now and this is what I see different.
Katana kit is
1. Auto (just suck on it and battery fires automatically.
2. limited to just one type of atomizer (510 thread)
3. Cheap compare to other styles of easier starter kits.
4. Leak will kill the battery since auto switch is open.
5. no upgrade path to CE style atomizer or any other with out an adapter, don't know if there are adapters avail.
CE style battery.
1. Manual. (most prefers over auto)
2. easy upgrade and compatible with 95 % of atomizers, cartos, drippers etc etc.
3. Very inexpensive if you know where to look. Eg, 450 MAH starter kits can be had for about 10 bucks.
4. Leaks will not kill the battery.
6. easy upgrade. (upgrade the battery and all your other supplies will work without wasting your hard earned $)
EVOD heads that I like are under 5 bucks to replace (replace the coild and they are about a buck each, rebuild yourself and its about 10 cents each) very cheap to run and care free. Ask if you get lost.
If I may ask , where are you getting your kit, juice ? Local ? online ? what kind of cost are you looking at?
Regards.