@
geeping, I haven't seen many (rare as heck) trailers with independent suspension, but there are a few.
It's a weighty matter.
Similarly they tend to mount low, on the axle.
That said my Travoy sucks on my 20" Dahon's and is a treat on the 622 wheeled road bikes.
Haven't tried it on my 26'ers or 16'ers or 12's.
but I don't like dragging upside down trailers in traffic, so will defer to what I know works.
Got the new hitch , like the QR , but it hits my light/radar (Thicker)