Using Canon's ultra-rare 50mm F1.0L

After trying Canon's 'holy grail' 200mm F1.8L, Lensrentals' Zach Sutton is giving another ultra-rare lens a go: Canon's super-fast 50mm F1.0L, first introduced in 1989. Find out if Zach thinks this lens is really usable, or more of a collector's item.