This perk is of questionable value unless already having the Swift Learner perk at level 3 and want to increase gaining of experience even more, such as for obtaining the level 30 achievements. Also neither of the experience-gaining perks have any benefit past the level cap, and thus they generally "waste" a perk slot.
Taking Swift Learner instead of this grants a permanent 10% exp boost with no matter of sleeping. But, being well rested along with having the level 3 perk will double this exp boost.
The Vault Boy image is similar to that of the Mister Sandman-one, excluding the murderer with a knife and the mattress. It shows the Vault Boy sleeping on a bed of spikes instead.
Beds flagged as owned (red name) cannot be rested in even with this perk, keep this in mind if scouting for a non-standard home to use with the perk.