How do these match up with GW elves? Size, style, usefullness?

They're very slender (which some people like, others don't) though the Palace Guard are a bit more filled out. I don't have a comparison image but here's some of the Mantic Elves on their own:




Palace Guard:

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concerning style:
To be honest, I dont see these elves fitting the style in which most lotr minis are made. These elves dont look very 'realistic' ,but more fantasy.

Lotr (movie) was designed in a way that it would look convincing enough to realy have happened, for that reason most armour and weapons, look similar to some warriors that did exist. (or in this case could have existed)
These Elves do not look like this. but that is of course my opinion , and what you sort of asked for.

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