If he wants to show you what he is using, I will leave that to him. Based on some information we talked about in PMs, this is what I recommended for him:
One of these blades:
1) Butterfly Primorac Off-
2) Donic Appelgren Allplay
3) Stiga Allround Evolution
4) Xiom Offensive S
5) Yasaka Sweden Extra
Rubbers:
Xiom Vega Europe on both sides or Vega Pro on FH and Vega Europe on BH
or
Tibhar Aurus Soft for both sides or Tibhar Aurus for FH and Aurus Soft for BH
But I think, he may benefit from more information from different people about subjects like:
- How you need different technique for a rubber like H3 than you do for a Euro style rubber.
- The process of boosting and why or whether it is necessary for a rubber like H3.
- Differences between Commercial, Provincial and National H3 and whether he will be able to tell the difference.
- How easy/hard it has been for different players who switched from Euro catapult rubbers to a rubber like H3.
My personal opinion is, if you start from the beginning with H3, you will be fine. If you start with Euro rubbers and try to switch to H3 before you are highly skilled at spin contact (tangential contact/ brush contact) and don't have the precision on this kind of contact or the skilled footwork to be in good position so you can take a good fundamental stroke, H3 can be a hard transition. Also, some people like the process of boosting. Others don't. So, Kai having some extra information might really be useful.
I know different people have different opinions. I also know, I can use Hard Chinese Tacky rubber without a problem. I don't need any transition time. But that is because of how I contact and years ago, that would not have been the case. I know, when I stopped using H3, my two reasons were, I started hating the fact that I needed to boost every few weeks to a month (to me that is just a hassle). And, because of how I contacted the ball at the time (not sure this would still be the case but it might), I was wearing a dead patch in the topsheet where I contacted the ball within 3 weeks of putting a new sheet on. The spot where I contacted would feel like anti-spin while the rest of the sheet was still tacky. But the rest of the surface area did not matter because where I contacted was not acting like tacky offensive rubber anymore. It was functioning as if it was anti-spin. This happened to me with Commercial, Provincial and National versions.
And, for me, when I switched back from H3 to Euro/Japanese catapult sponge type rubbers, my level jumped pretty quickly because, in some ways, they are easier to use.
Where does H3 shine? Short game for sure. Where else? If you have high level technique, precise brush contact, and can get into position for each shot with good footwork and use your body, behind your shot on almost every shot, H3 can be amazing. If you tend to hit flat a certain percentage of the time, H3 may not be for you.
And most people who start out with Euro catapult sponge with grippy (non-tacky) rubbers, it is likely a person playing for about a year, with no access to coach or club, will be making direct impact and not making spin contact.
But, other people's perspectives, especially people who started with Euro type rubbers and switched to Chinese tacky rubbers, would likely be helpful for Kai.