Here's another view of the Robert Smith track:

Robert Smith - Small Hours. From the [...] album Johnny Boy Would Love This: A Tribute to John Martyn comes a poignant yet incredibly lovely take on one of Big Muff's most haunting songs.
Dave Simpson

I've heard neither the original nor the cover, so have nothing useful to add!

what are the best tribute covers albums just discovered that Testimonial Dinner the XTC tribute is on spotify.

http://open.spotify.com/album/6uFdeM30ZkxSBEbjAHrLJ8

Any Other Good Ones ?

is a fantastic Gram Parsons tribute album, executive produced by Emmylou Harris. It features GP covers by Wilco, The Mavericks, the Cowboy Junkies, Lucinda Williams and David Crosby and some Emmylou duets.

Harder to find is Come and Get It, a tribute to Badfinger, with great stuff from Aimee Mann, The Knack, the Loud Family and Adrian Belew

His version of Small Hours:

A thankless task. Martyn's original, witching hour, al fresco, 'o'er the water' recording with geese honking in the background has such a powerful atmosphere that any cover version loses its eerie potency by default before a note is struck.

The song reflects an innate rhythm of the world, that of nature itself. For me it captures evocatively the trance-like state when we would normally be asleep in the wee small hours but instead lie awake, willingly lost in a calm almost out-of-body reverie, our senses attracted to the ambient sounds of nature (rain on canvas, a wind blowing through the trees) and our minds set adrift by them.

It's music to accompany such rare occurrences, the fleeting moments when we are held by a comforting stasis of time and space that is completely outside of human artifice as measured by a timepiece or four enclosing walls. Although the feeling is intangible, in those same moments we also sense it is something deep and ancient. We suspect the feeling has always been there in our DNA and will endure long after we have gone. That's how powerful Martyn's song is.

Or to put it another way, Smith's version is no embarrassment but it loses far more than it, or any cover, could ever begin to add to the original.

Just discussed it on Front Row and didn't seem particularly impressed.
The Snow Patrol track sounded bland but the Beck track was more promising. Dreadful title I can imagine his response and it would get a Parental Advisory warning.