as far as I can see from the pics, yep they are different. I am sure there is no difference in performance-wise comparison. Most probably, different suppliers, different molds or cheaper production techniques.
^^^
As above cup is the fastest since it is the lightest.
Still to me, the best is ph-1 though it looks ugly (I drive one so do not ballistic against me
. Raw + no intermittent electronic details.
Performance variation among the same spec RS's are mostly from the plenum and inlet manifold machining tolerance differences + driver.