USCs and SL8s being discontinued?

I wouldn't count on it. Just like the Mark 23, everyone claims they are discontinued every single year. Hk only sends a certain number over every year, and when they are all sold, everyone starts thinking their won't be any more...and the rumor only gets stronger as stupid gun retailers tell every potential buyer that there are no more to be had...therefor enabling them to jack up the price on any that they have in stock.