I've been through many different versions since I first read the LOTR (1972).

Mass market paper (The little ones): Very convenient if you're planning on reading at odd moments but will be practically unusable and/or will disintegrate after a couple of readings. I've bought many copies of these.

Trade paper (The big ones): Not as convenient to carry around but if you do most of your reading at home they can last quite awhile. Trade paperbacks are usually the same type size as hard cover and are very easy on the eyes. I bought 1 set of these to be "The last set I'll buy" and they were holding up quite well until I lent them to my son 4 years ago. He only just read them through in November and he commented that they were getting tired.

Hardcover: Lasts quite some time kind of a pain to carry around but usually the best choice for repeated readings and looking stuff up. I just received a 1 volume "Leatherette Collectors" edition for Christmas and it appears extremely durable and of high quality. I have noticed an illustrated hardcover 3 volume boxed set on Amazon recently which I may pick up that seems quite reasonable.

There are issues about accuracy of texts and such and this link may help you out:http://users.telerama.com/~taliesen/tolkien/editions.html He has pictures, isbn's, and information galore.

Enjoy...........