I tested so many rubbers listed by others here so maybe I should give my 2 cents here after all. Do keep in mind it's just my personal opinion so please don't kill me
To me no1 should ever use commercial/Provinicial H3s if he/she never boosts rubbers. They're really poor bang for buck choice if stay unboosted especially when compared to Euro rubbers at similar price. In contrast boosting H3s HEAVILY would transform them into monstrous performer both spin and speed which I actually really like. Totally different animal.
I recently tried 729's Battle II Provinicial and to me it's playable without boosting and still seriously powerful under hard shots (boosting still recommended though, flicks felt weird/tough without boosting due to super tackiness and tough topsheet). Also
bloody cheap. Throw angle is medium-low though (H3 is more like medium-high) plus Not sure if it's easily obtainable outside China. The commercial Battle II's sponge is very dead sadly just like H3's.
Big Dipper doesn't play like your typical H3s at all. Doesn't have the ultimate power against a boosted H3 and It's also a bit unforgiving with long low trajectories, stiff rubber+sponge combi and its super weight. Can work well though when paired with right blades.
Joola's Golden Tango is a very unique animal. Medium-low tackiness. Even higher throw angle than H3 and very easy to generate very strong spin with its topsheet. However there isn't catapult at all for any sort of threatening speed and the ultimate spin is also slightly lacking comparing to a boosted H3. A bouncy blade with good dwell would definitely help this rubber and u would be pretty much relying on topsheet alone to generate good power in topspin game.
Golden Tango PS (featuring Ryzer 50's sponge) would add considerable catapult (and a bit more spin imo) and throw angle less extreme (still very high), but a blade with stiff top layer is required for that sponge to function properly. Try putting it something with soft top ply such as Butterfly Mizutani Super ZLC and the rubber would become mushy, lack of control and less spin with soft shots.
Xiom Vega China is very good alternative and doesn't choose blades. Medium tackiness, high throw, not dead at all even with very soft shots. Best point about this rubber is its control it really does make the goes anywhere u want. Again doesn't have the ultimate power of boosted H3s but still pretty strong and rewards proper brushing techniques. Downside is as mentioned by some1, poor durability which is a common issue among the Vega lineup.
My personal recommendation however is the Andro Hexer Duro which I've just got my hands on. Despite it being almost non-tacky, has a super-soft sponge by Chinese standards at 42.5deg Euro scale ,has a hitting feel of nothing like a Chinese rubber and has a manufacturer spin rating lower than other Hexer variants, I managed to generate more spin than other Hexers in topspin games (excluding Hexer Grip/Powergrip which I haven't tried) and even very close to boosted H3 level under very hard shots (or more than my backhand's Aurus Prime if any1 cares). Throw angle also medium high like H3. Gears/catapult not too much when dwelling sponge hard but soft shots u're allowed to play variety of spin-rich attacks with minimal effort. Flicks are breeze as the sponge/topsheet wraps around the ball nicely.short games maybe a tad less spin but still real spinny and control/placement is excellent. In short it's a rubber that feels nothing like H3 when the ball sinks into the sheet (good or bad thing depends on you) but offers very-close to boosted H3 charactersitics/performance in topspin/short games, while being more versatile in other aspects. Or u can say it plays like a way better version of unboosted H3.
To conclude the above mess, my suggestions for H3 alternative (without boosting) would be:
Best: 729 Battle II Provincial ver. for max power / Hexer Duro for a (almost) boosted-H3 performance/characteristics. If you can find one that is.
2nd Best: Vega China if you can't find either of the above, or u prioritize highly controllable strong topspin shorts over ultimate power.
3rd Best: Golden Tango / Tango PS, if u don't mind hard rubbers and love brushing-style spin shots, backspin sidespin topspin whatever, over everything else.
