A long time since the last reply, but as I have spent a great deal of time researching the subject and spending a bit of money in the process, here is my bit of experience.
I first became interested in luxury bedding, linens and towels after visiting few boutique hotels in New York few years ago but as I was still fresh from Uni I was not really ready to upgrade at home...
Anyway, I recently decided to review all my bedding/towel situation and here is what I found:
First the material, it must be 100% cotton, actually long staple cotton. Egyptian(also known as MAKO) is the absolute N.1 but Supima/Pima is a good alternative.
Thread count is important, but must be linked to the material above and woven by a respectable factory.
Anything above 200TC gives you already a soft sheet. I have found 400tc to be the best as when you increase above that, it becomes increasingly difficult to maintain (at 540 was already too complicated).
I have 4 sets so far (duvet Cover, Fitted sheets and pillowcases), the first is a Marks & Spencer's Autograph 400TC Egyptian Cotton set woven in Pakistan, the second a secondary brand (Catherine something) 400TC Egyptian Cotton woven in Egypt, one that I bought from Costco here in UK is a Pima Cotton 540TC and the last is from an Italian Factory that makes set for designers, which I managed to buy off ebay Italy, again 400TC woven in Italy, one sateen.
For what I have found so far, Pratesi, Bellora and Frette are all great Italian Brands as Yves Delorme is a great French alternative. There is another great brand that only sells to 4-5 stars hotel which I am try to source but it looks difficult (more later).
Some of the things sold in US as Italian (e.g Sferra, Anichini etc), do not actually exist in Italy and may well be stuff that is manufactured by one of the above manufacturers and sold by a different name. Frette 200TC seams to be an entry line, but try to compare their 400-600tc with the competition and then tell me that these are not good.
So I have contacted the factories in Italy but they told me to be trading only with hotels/restaurant or big retailers. There may be a chance to buy a small bulk from them, but personally I would only need max 3 set and do not want to start a business selling the rest off ebay... however it could be an idea if we can get together and make one order as the price per unit could be almost half of what retailers here in the UK offer for stuff made in India or Pakistan.
Anyway, what else did I find? I have bathrobes and towels from Frette (bough very cheaply in Italy) and towels from Yves Delorme (bought from Selfridges in London) and are great, actually incredible. But I have also other 100% Egyptian cotton towels bought at Costco UK which are very good.
Pillows and duvet: Brinkhaus seams to be the top brand but have not experience with them. Instead I have experienced the products by Northern Feather ( NF Canada and NF Ireland were the same company but not sure it is still the case), both in hotels and now at home and have to say to be top class. As Natural filling, in order from best to good, Siberian goose down, Hungarian Goose down, white goose down and Goose Feather and Down are the choices. Clusterfil Ballfibre seams to be the best synthetic alternative to down (I have two great pillows filled with that material). I would recommend both standard and square pillows (26" x 26"). Northern Feather sells in the UK under three brands, "Night Flight", "Irish dreams" and "Comfort Zone".
In terms of beds, Vi-spring is the top choice in UK and most probably superior to other brands. (John Lewis carries some affordable model from them)
Sealy and Simmons are two top US brand that supply many top hotels (e.g Sheraton and Westin famous beds). However these seams to be manufactured in the UK under some sort of license agreements, using some of the same patented technology but not all models.
Sealy Ultra Luxe Pillow top models are great and probably what I will go for. Simmons' Beautyrest, which I would have considered as an alternative, are not available in the UK.
Some of the above can be easily researched further by googling...
Let me know if you are also interested in getting affordable Italian woven sheets directly from the factory as we could together achieve that.