I bought 400' reel of 5285 (Ektachrome 100D) some time ago and sold all other slides since I've started using it.
It has no expiration date and the results give a very slight magenta look (that can be compensated with a green filter anyway), but they look rather 'a bit retro' than 'magentised', especially if shot in the city. Anyway, performs still much better that Elitechrome 200 I had frozen for a while.
A perfect slide for a holiday!