I have a Florida 5.0 cluster in my 1991 GT.  I bought it quite a while
ago, but it looks like the prices have gone up since then.  When I purchased
mine, I just got the blank panel and purchased the gauges separately.  
Everything went about as well as can be expected with only a small amount
of trimming of the steering column shroud required to get everything to fit.
Wiring was a pain in the butt, though that's to be expected.  I went with
an electronic speedometer since I've had too much bad luck with cables going
bad.  The Auto Meter speedometer sending unit is a little on the bulky side
and something of a pain to get in the transmission, but it's not that bad
and definitely worth the effort.

As far as the transaction with Florida 5.0 went, I have no complaints.  I
found them to be polite and quick, plus quite helpful in getting the exact
panel I wanted made.  I went with one that is basically the same as their
CDE-687A model, but I had them install extra lights to handle the various
idiot lights for oil, alternator, coolant level, etc.  The bigger problem
was coming up with a provision for the "check engine" light, which is
required to pass emissions in California.  Ultimately I found a panel mount
12 volt light assembly with a flat bezel at the local electronic store and
glued the original label to the front of it.  It looks a great deal better
than it sounds, and passes inspection just fine.  But it's something to
consider if you're going that route.

The big difference I can see between the MC Machine one and the Florida 5.0
one is that the MC machine panel is just a big flat plate, whereas the
Florida 5.0 one is actually a formed piece of plastic that has some depth
to it.  The flat panel one would set the gauges back farther, which would
be a little bit better since the Florida 5.0 setup pushes the gauges towards
the driver enough to create an irritating reflection in the windshield at
night.  It looks like you might have less work to do gutting the dash
behind the gauges with the Florida 5.0 model, though, which is a worthwhile
consideration.

All told, I'm pleased with the one I ordered from Florida 5.0 and would
willingly order from them again.  But be advised that it does take a while
to do the gauge rewiring if you want to keep it neat and tidy.