How do you know if you have the reputation bonus in Mist of Pandaria Classic ?
At the moment I can’t find any visualization in game that shows if I have the reputation bonus Active or not… So right now I have been purchasing the item off the reputation vendor, multiple times to ensure that I have it active.
I hope I’m not the only one who find this really inconvenient and I would hope that Blizzard could add some kind of visualization in game, for this 
Buy item on one char, click it once, you have it forever on all your other chars.
The visualization is when u get any amount of rep and it says (+bonus rep).
But then I have to hand in a quest, just to see if the bonus is active on that character or not - This is the whole point of having a visualization in the game, so you don’t have to hand in the quest to see if you have the bonus…
Please, don’t try to justify this with an illogical response.
You already know you have the bonus once you activate the item, because it says:
" Unlocks 100% bonus reputation gain with the Tillers for all characters on this account."
What else do you want? A neon green rep bar?
It’s probably possible to check by using a script. I dunno, but I’d imagine it’s how you would be back to check it. Although the loss of rep from a single quest doesn’t really seem like that big of a deal if it confirms it for you for your entire account from that point forward. 
No - and unfortunately I did not get this message you’re referring to in-game. But back in the days, in original Mist of Pandaria… We had a small arrow that indicated you have the reputation bonus.
he wants a passive ability in his spellbook general tab, the info that tells you which flying and pet battle training and such
The early survey tweeked the option to stay in MOP or make some sort of transfer to other versions of wow. I think they will keep releasing the classic expansions just for the sake to keep “something to do” for the players. It’s their way to cicle between wow versions during the patches of retail
Just turn in any quest and check your XP log. It should say something along the lines of " +300 rep with X (150 rep bonus)".
Alternatively, you can turn in a quest and see how much it is supposed to give on WoWhead. If you get double, then it works.