Daniel - The one early mono Coltrane 'Atlantic' that I have is a 'Giant Steps' UK first issue on the London label. This one is a DG mono and its sound is easily the best of any Coltrane Atlantics that I have heard to date, so I am a convert to the monos. Very big, powerful sound - almost like a Blue Note of that vintage. I've got the 'Heavyweight Champion' box on vinyl and that sounds pretty good to my ears but if you can find those early monos in good nick for a reasonable price and especially on UK London, I say - go for it !
The first press US Atlantic issue for the 'Coltrane Jazz' would be black label, I guess?