Along with the other names mentioned in this thread, Franz Brueggen
has been active in recording Haydn symphonies, though I don't know if
a "complete" cycle is in the works.  The integral set of his London
Symphonies (I assume it is recycled, but am not certain) is out, and
I just recently picked up his new release of the Paris set.

Overall, my impression of this Paris set is very positive, with the usual
attributes of Brueggen's Haydn performances (with the HIP Orchestra of the
18th Century) in play.  I'll see if I can't submit a more detailed review
later, especially after I get a chance to compare this set with my other
touchstone Paris sets, Kuijken's and Bernstein's.

Also, inside the booklet of Brueggen's Paris symphonies is mention
of a volume of "Sturm und Drang" symphonies.  I don't know WHICH S&D
symphonies--my searching so far among US-based record retailers hasn't
revealed any more information, however, so maybe it's not available as yet.
This set is performed with the Orchestra of the Age of Enlightenment, the
same one that Kuijken used for his Paris Symphonies.

As for Hogwood, I continue to enjoy the few London Symphonies he recorded
in the 80s with the Academy, and I have several volumes of the integral
set he had been doing in more recent years.  While I don't think everything
he has done with these recordings is without peer, there are a number of
performances I quite enjoy--take Nos.  6-8 (the Matin/Midi/Soir trilogy)
for example.  By sticking to about the same number of players that was
known to have been in Haydn's orchestra at Esterhazy, Hogwood brings these
performances out with a nice sense of their original proportions.  Instead
of regular "symphonies", these works take on their truer nature, more
as examples of Symphonie Concertante.  The interplay between the
instrumentalists and the differences in the orchestral colors (try the
trios to the Minuets, where the bassoon, contrabass and cellos have
independent solo parts) tell me that Haydn wrote these works to celebrate
his new found joy at ending up as the director of these extraordinary
players in the Esterhaza band.  To my mind, Hogwood is able to recreate
this atmosphere.

The lack of a keyboard continuo in Hogwood's performances seems to be
controversial.  He does use a fortepiano in his 80s recordings of the
London symphonies (it can be easily ignored, as it's often overwhelmed
by the orchestra), but forgoes one entirely in even the earliest Haydn
works.  I personally don't miss the keyboards, especially when compared,
for example, to Dorati's version of the Matin/Midi/Soir trilogy--in that
recording the harpsichord is horrendously overmiked, making it sound more
like the accompaniment to a 70s pop song than anything else.  Given the
alternative, I'll take Hogwood.  But I would like to hear what Brueggen
might do with the same works.

Bill H.