Impressions after several practice session (H8 on FH + Nexy Calix):
a) tackiness - it is a mildly tacky rubber, the level of tackiness is nowhere near N3 Neo. Which for me translates into slightly worse short game, and not as much spin on "brushy" serves. But still, H8 is much less bouncy than pretty much any modern tensor rubber.
b) driving the ball - easier with H8 than H3 Neo because H8 is less tacky. Same considerations apply to passive blocking.
c) looping - the grip is good, quite reliable, but one needs to engage the sponge a bit more when looping using H8 in order to generate the same amount of spin as with H3 Neo. The arc is a bit lower than with H3 Neo, as noted by other reviewers. Looping against backspin requires more effort using H8 than H3 Neo.
d) speed - at medium swing shots H8 feels a touch faster than H3 Neo, but at full swing H3 Neo is faster and spinnier.
If you want to see H8 in action, here is a video of a practice session using Nexy Calix with H8 on FH and 5Q+ on BH. I'm the player in orange shirt.
Video segments relevant to this review:
22:00 - alternating FH/BH loops against block
26:30 - FH to FH drives
29:50 - FH loop against block
First match of the season using Calix 2 and H8 on FH.