I bought a set of Tacx replacment 11-tooth jockey wheels to replace a broken lower pulley on a Deore 9sp RD.

After inserting the correct bushings to match the size of the Shimano fixing bolts, I noticed that the Tacx upper jockey wheel had no side-to-side float whatsoever. In fact, other than having "Upper" stamped on it, the jockey wheel appears to be identical to the lower wheel in every way. My understanding is that the upper pulley needs to float a bit to allow good shifting. The original Shimano upper wheel does have very noticeable side-to-side play.

Has anyone else noticed this issue with Tacx wheels, or did I get a bad one?

Fortunately the existing Shimano upper wheel is still in good shape so I left it in place, and only replaced the lower one.