In terms of quality, these ropes are Martin ... need I say more? Irreproachable manufacturing, balanced sound, good material, popular with professionals. The pulling "extra-light" is recommended for play twelve strings with little risk cramps. If you record in the studio, rather considering a draft "Light" that will give you more shine and volume at the cost of significantly more painful crossed to place. Beware strings Sol extra-light: they tend to break very easily and you should be extremely cautious in granting them. Ideally Martin thinks slide in a replacement in its packs. Practicing twelve strings for 40 years, I know that nothing is more annoying than playing only eleven strings ...