This is going to be a quick review... don't buy them.
We were in Muir Pass Hut on the JMT at >12000 ft. Chatting about food, someone gifted us a pile of almond butter and Jelly... Let me say that again, someone gave us food they had carried to 12000 feet... As a backpacker this should seem surprising and odd.. Why did they do this?
Because they were leaking all over the place! We figured we didn't care, and in fact carried them a ways without them leaking much (after they weren't very full). That said, if you "overtightened" the lid of either (that is, if you got it even near tight) it would pop past the threads. The backs of the tubes surprisingly didn't seem to leak, but the threads at the front were just crappily made.
So, what should you use instead?... Anything else. How about a plastic jar from cheap peanutbutter?
Actually, On second thought... do use them, and give them to me at 12000 feet :D.
(These tubes have been safely disposed of in a trash can).