That said, its pretty damn hard to make a decision based on buzzwords that people are throwing around. See and feel the fabrics, then decide.
Since there doesn't seem to be a consensus I think this is probably the best approach. Thanks all!
"Sea Island Cotton" - is cotton that is harvested on the Sea Islands off the coast of Georgia, U.S., and when properly woven and finished could feel as smooth and luxurious as silk. It is the longest cotton fibre, and although it feels very delicate it is extremely durable - resulting in clothing that could last a generation or more.
Egyptian cotton is cotton that is grown in Egypt, and if woven and finished in Switzerland could result in a fine product - but will never feel as silky as Sea-Island cotton.
I know this is an old forum, but when I read some of the replies, I just had to jump in. I'm a historian from the town where Sea Island Cotton originated so I've done some extensive research on the stuff. Here's a rundown:
True Sea Island Cotton no longer exists today. First introduced by William Elliot in the very late part of the 18th century, he brought seeds from Barbados and began planting the crop on the outer islands off the coast of South Carolina, not Georgia. By cross breeding to attain longer, softer fibers Sea Island Cotton was born. Its quality far exceeded today's Egyptian Cotton making it the finest cotton on Earth. Eventually as the crop grew in popularity, planters did later begin planting in along the outer islands of Georgia as well, but strictly to what's today considered the "lowcountry". The greatest concentration of Sea Island Cotton plantations were found in Beaufort, South Carolina making the plantation owners there by far the wealthiest in the region. Sea Island Cotton was praised for its light, silky texture was almost transparent in appearance and was primarily used for making men's shirts and ladie's nightgowns/undergarments. In 1917, the lowcountry was invaded by the boll weevil and is held responsible for driving the precious crop to extinction.
If you were to come across a Sea Island Cotton product today, understand that the term "Sea Island" cannot be regulated! Barbados Cotton is its closest cousin and still is finer than Egyptian Cotton. For example, most Barbados cotton shirts retail around $230.00