Me and my buddies visited it on May Day holidays during our leisure trip to Vladimir.
I wouldn't like to chew the same fat, so I'd just add that, firstly, its territory is easily accessible by car and, secondly, there's a good - and legal! - chance to avoid paying an entrance fee.
So, firstly. One should drive behind the ancient Cathedral of Saint Demetrius, proceed to that Holy Assumption Cathedral, climb a small hill it stands upon, circumvent it clockwise and - here you are! - find yourself on a large parking place to leave one's car literally a couple of meters away from the main entrance.
Secondly. The cathedral is both a place of worship and a museum. Hence, when one enters it as a laic then he/she must buy a ticket whilst one does it as a believer, he/she, naturally, pays nothing. A simple recommendation: do it the latter way. In this case you'll save a couple of bucks and enjoy the razzle-dazzle of an Orthodox Christian liturgy.
You are welcome!