Just been a round-trip in T4, agree with the lack of walkways and the sense of having to walk infinitely. Very vibrant decoration, feel less crowded than T1-3 (maybe because it's noon arrival and midnight departure), but perhaps less exciting than T1-3.

I also asked the airport counter that (at least) Cathay Pacific passengers are allowed to go from T4 departure to T2 "as long as enough time"; but I entered the departure area just 1 hour before boarding (and before checking out the CX lounge) so could not try.