Something I've come across recently.
Can anyone with experience share their opinions on this?
Some say they like the control and others say it's not a fast enough rubber for BH.
Lots of control, and not fast enough are exactly the reasons for and against H3 Neo on backhand.
H3 Neo is a comparative hard rubber with very little catapult, making it both relatively dead to a front on contact with the ball and very linear. Both things that tend help control. Tackiness with it's slowness also helps with short touch play.
On the other hand, catapult tends to help power your shot when you are not taking a massive swing at the ball (which is pretty much all backhand shots) and allows you to play an aggressive stroke with a relatively small/weak stroke. A less dead rubber is also faster on the block, which means you can more be more aggressive by simply placing your blocks well, without having to offer much of a stroke.
It comes down to what you are looking for in your backhand rubber. (or for that matter any rubber)
People who are looking for control and linearity for consistency and the confidence to play a bigger stroke on the backhand and still be easily able to control the shot might like H3 neo.
People who are looking for a little bit of assistance on a less than maximum effort backhand (which is pretty much all backhands) and want more speed/spin for less effort will prefer something softer and with more kick.