Janner,

I have played the Martin recently and I found it a bear to play. The neck was heavy and the set was kind of high so it was hard to fret at standard pitch. With the higher action it went out of pitch when tuned down. I have played D 12-20s that were a joy to play and hear.

I don't know about the Gibson at all.

The very best 12 string guitar I have ever played was a Guild. And I have a friend with a J-30 12. Nice action great sound, trim but sturdy neck.

Don