Don't worry really, just lick/peel & stick and provided that the film is wound tightly around the spool as it should, the backing paper alone protects it. Like you the first time I used a film that wasn't contained (35mm can, 126/110 cartridge) I was shocked that nothing but a band of paper protected my film but that's all it takes really. The 120 film containers are big and bulky and don't really offer much extra protection but if you feel like using them or just want some M&Ms, go right ahead!
As mentioned above, Provia 400X is the only 400-speed chrome film left. I used to shoot the 400F version and Ektachrome 400 on occasion and generally preferred the Fuji at that speed though I used E200 normally. Now I mostly shoot C-41 for color work where Portra 400 is excellent, such small grain unless you push it to 1600 that you hardly need to use Portra 160 in medium format unless you make really huge enlargements.