The replacement ratchets with more than 18 teeth get progressively less rugged, they have to. Smaller engagement surfaces for same torque.
General advice on this seems to be that 18 tooth stock ratchet is always the best choice for reliability if failure would be catastrophic, but 36t is a popular happy medium. The mechanism isn’t the same as a pawl hub, you’ve always got a bigger torque transfer area so more efficiency than might be expected but they aren’t tooth:point comparable in simple terms. More teeth will still give faster engagement and therefore quicker response to sharp inputs in technical terrain.
If you’re uncertain about the hub you have, simply pulling it off and counting the pawls is the sure answer. An M1900 at full retail should be 3-pawl, but it’s possible an OEM unit might have an older/cheaper hub. The 2pawl and 3pawl aren’t compatible at all. The 3pawl has the pawls where you would expect to find them on a Hope for example (in the freehub). The 2pawl has the pawls on a shaft that’s part of the hub body and the driven ring is in the freehub body instead.