I have sold a bunch of these to folks for syncros with no real problems.  I
have only installed these on non-syncros myself (New Jersey has like three
syncros and none around here).  The biggest problem people have with these
headers is not installing them correctly.  The instructions clearly say to
put everything together loosely and then after everything is installed
tighten everything up.  However most people (including myself) have ignored
the directions and just put them on tightening as you go.  They will not fit
properly this way, and you will swear that the pipes are not bent, right,
etc.  If you do it in the proper way you should have no problems.  

I would recommend buying them through me.  I have them in stock, it is $280
for the complete header with muffler, and if you did have a problem you could
just call me for tech support.  Most of the people who were complaining and
upset bought thier headers through S&S directly and thier customer support is
poor.  If you had a real problem with one that I sold I would send you a
replacement and then deal with S&S myself.  

One cool note, S&S is offering a ceramic coated header as an option now (you
can have the muffler coated too, but I don't have the price for that).  I
have sold a couple of these already and they are actually very beautiful.  
They look like stainless steel and one list member has installed his set and
has a few hundred miles on them with still a nice look.  The ceramic coating
place also bubble wraps the systems and puts a goodly amount of newspaper in
the boxes to protect the systems (S&S never packs these things properly).  
The ceramic coated header is an extra $110, or $270 instead of its normal
price of $160.  Also the ceramic coating has a lifetime warranty.  Just FYI.

Thanks,
Ken Wilford
Van-Again
John 3:16