I have only ridden the Talgo equipment once, back in
1994, when it was on demo runs here in the US. We
rode a circle trip from Oakland - -Suisun - Sacramento -
and return via the Valley. We rode the Talgo on the way
east, but had to ride the SP coach on the way back. (The
SP equipment was their 1950s lightweight coach and the
Sunset Limited "French Quarter" lounge -- very nice!

I found the ride in the SP lightweight coach from the 1950s
to be FAR superior to that in the Talgos. The Talgo car
swayed side to side most annoyingly EVERY time it ran over
any imperfection in the track -- which was most of the time.
The Talgos have "passive pendulation", unlike the Swedish
X2000, which only tilts when it needs to in order to go around
curves faster. (No, I have never had the pleasure of riding in
an X2000 train.)

I found the ride quality of Superliners to be FAR superior to
that in those overrated Talgos. Too bad, much too bad, that
the folks in the PNW did not choose to purchase X2000
equipment. (Those things can shave 30-40% off trip time
by going around curves faster.)