It was easy for me as an HR person, I could see who had availability at any time of day or night so it helped my department make sure we were always covered when needed! The only thing i dislike about this program in general would be its price point but thats because you are paying more than what other similar programs offer (like Recruiterbox).
If your looking into using flexshift then go ahead give them call they will walk through everything step by stepp if need help!! We have been able solve our issues regarding not having enough people available during certain times throughout shift changes/holidays etc..