The unique feature of these two albums is that they are compilations. If you don't have any of their earlier albums, these will be the ones to get. So Far was available on compact disc a long time ago but not the Celebration Copy. This vinyl record is rare and I've seen copies being offered for sale on Internet sites for STG45.
BTW, what's your favourite Crosby Stills & Nash track? Many people would say Suite: Judy Blue Eyes but in terms of harmony, there's nothing that can match this song. They might have passed their most popular period by the time they appeared on this show but there's no doubt in my mind that their harmony surpassed many other singers or groups. Here is Helplessly Hoping