I bought a sheet of Mantra Pro H during Aliexpress springsale for 27€ and tested it on the backhand side of my trusted AJH TMXi Pro.
Without going into much detail, this is one of the best if not the best rubber in terms of price-performance. It does everything very well without excelling in any department. It is just very balanced, good speed, good spin, easy to block, easy to receive. No wear of the topsheet after a few sessions.
If you are tired of EJ‘ing and just want to settle on a cheap rubber that has good performance, mantra pro H is perfect. It costs around 50€ in most shops in Europe, just saying
I have recently put on a sheet of Mantra Pro H (Violet) on my AJH TMXi Pro, and can confirm all of your descriptions.
Some background: the backhand has always been my weaker side, and I have never quite found a BH rubber that I'm fully confident in like I am with H3 on FH, especially on limba inner-carbon blades that I'm so fond of. Viscaria-type blades, in my personal experience, are far more comfortable on the BH side, making the set of viable BH rubbers for them much larger. Inner blades, though, tend to be more picky with rubbers. In the last 6 months I have experimented with Rasanter C53, Prov H3N 38° (boosted), H8-80 (both unboosted and boosted), and Sanwet Target National (soft 37° version for BH) and neither felt like a perfect fit. ESN-made rubbers can act too unpredictably for my taste and their durability tends to be iffy; H3 has superb spin and control, feels wonderful on perfectly-executed full swings, but I'm not good enough to be able to exploit that all the time, especially during match play. H8-80 felt like a compromise, allowing for easier access to speed, but its sponge didn't have the top-end power of H3 and the topsheet was much less tackier than H3, which didn't help with control. STN 37°, for the lack of a better word, was a rather weird rubber; It wasn't super tacky (couldn't really hold the ball in the air), but it was surprisingly spinny and in many shots it would feel very slow. Then it would sometimes become surprisingly quick (usually on loops), but not in the predictable way DHS rubbers tend to act — controlled on less powerful shots, powerful as you add more of your own power while adding spin.
So that journey led me to give another try to non-tacky BH rubbers, and so far (3 sessions in) it has gone pretty well. Mantra Pro H feels softer than 50°, is much easier to play and has sufficient power, nice feedback and a pleasant clicky sound on powerful hits, good control and stability, while being surprisingly linear for a grippy high-tension rubber. As expected, compared to Chinese tacky rubbers it requires more attention and a lighter touch in the serve/receive game to keep the ball tight, though it is manageable. The only shot that I am struggling with is the BH flick on short balls, as I'm more used to the feeling of a tacky rubber grabbing the ball for me and creating a safe arc. So far I have a tendency to overshoot on those shots, but I suspect that will eventually fix itself as I adapt more to Mantra Pro and adjust my technique to engage the sponge further on BH flicks.