From browsing/reading a few minutes at each site:

SAMPA tries to be world-wide, and is a collaboration of many people. Its
date of last update is quite recent.

Evan Kirshenbaum has plainly put a considerable amount of effort into his
scheme; he has several appendices for reference. He says his emphasis is
more on English. Apparently, his site has not been updated recently.
(These are dilettante comments, surely unofficial!)

=== more ===

On Mon, 24 May 2004 12:13:13 +0200, Marco Cimarosti
<marco.cimarosti@...> wrote:

> http://www.phon.ucl.ac.uk/home/sampa/home.htm

The SAMPA Web site suggests obtaining the WGL4 fonts, a very good idea.
Unfortunately, Microsoft no longer offers them as a free download. I
assume they are included (if implicitly?) in a Windows 2000 or XP
installation. This is also probably true of the huge (23 MB, iirc) Arial
Unicode font.

The WGL4 collection (WGL = Windows Glyph List) contains many (all?) glyphs
needed for all European languages, including Cyrillic and Greek
characters. To learn more, Google on [WGL4]. It works nicely with Unicode,
afaik.

Arial Unicode is a font that encompasses a lot of the BMP, as I understand
it.

One is tempted to disregard copyrights in this situation, and offer
private copies. (I'm not likely to need them.)

My regards to all,

--
Nicholas Bodley /*|*\ Waltham, Mass.
Opera 7.5 Release candidate (3778), using M2