Very interesting - though I would have to note that this has the very common limitation that it won't function when trying to restore specific databases to Server B after Server A is completely unavailable (and other similar situations), since there won't be an msdb with valid history.

Likewise, I would be concerned about cases (SQL2005, primarily) where msdb has incorrect path information, i.e. http://connect.microsoft.com/SQLServer/feedback/details/306604/physical-device-name-not-captured-correctly-in-msdb-dbo-backupmediafamily.

Question: did you test it with empty transaction log backups (i.e. LastLSN = FirstLSN) - for instance, a server set to do very frequent T-log backups that, for whatever reason, had no activity during that time. I usually generate those test cases with once-a-minute T-log backups on a development server with absolutely 0 activity.