The Michael Miller review posted by Fortunato refers to a CD version of SYM's O'Neill/Allan website, which is separate from the Carolan stuff. (Kat has provided the link above.) This website didn't seem to work quite right for me - for instance the list of O'Neill reels runs to several pages but I could access only the first.

Not sure on what basis Miller thinks Allan has "more vibrant" tunes than O'Neill, since it runs to a comparatively meagre 120 tunes, most (if not all) of which are in O'Neill anyway.

It looks like SYM are on safe enough ground concerning any copyright in the Allan collection. I have a copy which I bought in Dublin 30-odd years ago (but priced in UK decimal currency - 25p - so post-1970). The tunes were "selected from all sources," "arranged by Hugh McDermott," and published by "Mozart Allan, 84 Carlton Place, Glasgow C.5." But even with the tunes annotated with McDermott's useful bowing and fingering guidance, the collection is not marked "copyright." Maybe the publisher just missed a trick there. A companion edition, the two-volume "Irish Pianist," which I got at the same time, is indeed copyright. This obviously contained more original work. It has the same 120 tunes, "selected from all sources by Hugh McDermott and arranged for piano and piano accordion by Ian McLeish."