I have now five ball lock kegs from 3 different makers. Being new to kegging, I have a few question regarding the posts and poppets. I know that the poppets are not all the same. Four of my kegs are from other people. How do I know that the posts on each keg really are from that brand of keg? Will Cornelius posts thread onto the Firestone kegs? Should I standardize my kegs and trade for all one type?