I have been using the Hitec 805 when first started making them. They are ok servos. I am using them in 1/4 scale as steering and throttle servos with no problems except that I break the output gear right off. The 805MG is much better and the 5805 is digital with better power. I wouldn't recommend them for a Rebranded losi 5t throttle servo, Nylon gears can't handle the shock load. I suspect that this 900t servo is a off branded china one. The internal gears on a true 805 don't damage inside like this one did. I don't see no brake stiffener or alloy diff mount which contributed to the internal damage of the servo. In layman terms FLEX damaged the servo gears. If it was a true hitec 805 servo the servo horn would have broke off. I did look up this servo and it didn't have any replacement parts which proves that it's not a true Hitec 805 servo. But since you say it is then the OP can buy the replacement gear set for the 805 servo and fix it.
You should have showed the whole post from rclagescale.com for all to see. There's always two sides to the story and you omitted the other side.