On the basis of my own observations and reference to Dr. Graham's Remembering Revell Model Kits, I can confirm that EPinniger has the story straight. The Revell Kearsarge and Alabama appeared initially in the same year, 1961 - presumably to capitalize on the Civil War centennial that was sweeping the U.S. at the time. The Alabama kit, however, quite clearly was a modification of the Kearsarge. The latter kit represents the real ship reasonably well - as she appeared in the 1880s. (That article on the Steel Navy website is indeed excellent.) The Revell version of the Alabama actually looked fairly reasonable in the context of what was known about the ship in 1961. Since then, however, quite a bit of additionaly information about her has turned up - including two contemporary models and a couple of photographs that weren't known at the time. Those sources make it clear that the Revell kit doesn't look much like the real ship.
I left the Revell U.S.C.G.C. Eagle off my initial list. The story of that one is a little more complicated than EPinniger indicated - though he got the gist of it right. The kit made its initial appearance under the name Eagle in 1958. By the standards of that era it was a remarkably detailed kit. Unfortunately, though, it's pretty clear that the Revell designers made a mistake that several other kit manufacturers made. They based the kit on the set of plans drawn by Harold Underhill. Mr. Underhill was a fine draftsman and modeler; he included those plans in his book Sail Training and Cadet Ships. The Eagle, under her original name Horst Wessel, was one of four near-sister ships built in Germany during the late thirties as training ships for the Kriegsmarine. They were extremely similar, but all four of them were of different lengths. Underhill was completely up front about that; the text of the book clearly explains that the drawings are based on the plans of the Gorch Fock, which was about twenty feet shorter than the Horst Wessel. Unfortunately various dealers sold the plans with the name "Eagle" on them. The Revell kit is a reasonably accurate model of the Gorch Fock (later renamed Tovaritsch, when she was taken over by the Soviet Union), with the addition of some 1950s-vintage U.S. Coast Guard gear (small boats and so forth); apparently the Revell designers also worked from some recent photos of the real Eagle. Much later, Revell Germany re-released the kit with the name Gorch Fock.
To my knowledge, the only Eagle kit that has the right hull proportions is the 1/200 one from Imai (which I did put on the list). All the others - plastic and wood - that I've seen appear to have been based on the Underhill drawings. That's a shame. Neither Underhill nor the Coast Guard was trying to deceive anybody - and I don't think Revell was either. The same can't be said about the next chapter in the story.
The Revell "Seeadler" was initially released in 1960. It's a modified Eagle kit with additional yards (to turn it from a barque to a ship), a couple of deck guns, and different boats. That kit is nothing more or less than one of Revell's marketing ploys; it bears little if any resemblance to the real Seeadler.
The U.S.S. United States was a sister ship of the Constitution. So far as I know, all extant evidence indicates that the two ships were built to the same plans - with one big exception. The United States, apparently with the idea that she would serve as the fleet flagship, had a "roundhouse," which amounted to a raised poop, aft. As I understand it, no contemporary plans showing that feature in detail have survived (though Howard I. Chapelle included a reconstruction of it in the plans in his classic book, The History of the American Sailing Navy.) The 1/96 Revell United States kit, released (according to Dr. Graham) in 1977, did include extra pieces to make the raised poop; I guess the transom also was changed. I never had any inclination to buy it, but since the extant information on the differences between the ships is so scanty I guess it can't be said definitively that there's anything wrong with it. Revell also reissued its little 1/192 Constitution (which originated in 1956 - the company's very first sailing ship) with the United States name. As I understand it Revell didn't bother to add the raised poop to that one; the Andrew Jackson figurehead got replaced with a billethead and the name got taken off the transom, but otherwise the original kit was unchanged.
In another thread recently we talked at some length about such marketing tactics. Some people take a relatively benevolent view of the matter, arguing that Revell's target market was made up primarily of youngsters who didn't know - or care about - the difference. (The initial release of the "Seeadler" contained a "Message to the youth of America" from the Seeadler's captain, Count von Luckner. I wonder if, when he wrote it, he had any idea that his message was going in a box containing a modified Horst Wessel - or Gorch Fock, depending on how you look at it.) Maybe so. I continue to maintain, though, that such tactics are deceptive and fraudulent - and there's even less excuse for them nowadays, when the plastic kit market consists entirely of adults.
When I was working in a hobby shop (more years ago than I like to remember) I was in the habit of telling customers that "most plastic sailing ship kits are junk, and most wood sailing ship kits are worse." I agree completely with Papillon; I've gotten into the habit of referring to Mantua, Mamoli, Amati, Artesania Latina and their ilk as the HECEPOB manufacturers. (That's Hideously Expensive Continental European Plank-On-Bulkhead.) Believe me, Forum members, you don't want to hear what I think about those people.