I, of course, knew nothing about Mr. McGlinn personally (except DR Elmore's bits and pieces the bulk of which are being saved for his memoirs). But I do know that his CDs of SHOW BOAT and BRIGADOON are often played and hugely enjoyed.
I think the SHOWBOAT and the BRIGADOON are the best things he recorded.
If I may I would like to add
Anything Goes (Original Broadway version with dropped songs)
Kiss Me Kate (Complete recording although I am not crazy about all the singers on it)
Annie Get Your Gun (Original Broadway version with Kim Criswell)
Sitting Pretty (A great studio cast Judy Blazer, Davis Gaines, Jason Graae, Paige O'Hara, Roberta Peters, Paula Laurence, Beverly Lambert)
He made an attempt to record original complete scores that had never been done before
add: Broadway Showstoppers