There is a huge controversy brewing over this right now. The United Kingdom, Italy, Netherlands, Turkey and others all participated in its development and funding but the US Military has bocked at delivering them. There is a good chance that in the end parts of Europe will get the naval and convientional variant, but not the STOVL ( I miss spoke earlier, its STOVL, not VSTOL....duh. LOL @ me.). Its just an opinion but that seems to be whats happening....they are sighting national security reasons for not releasing the STOVL....we'll see.

here's a run down on the different classes of the F-35.