Just knowing it's in your mempool isn't a very strong guarantee that the payment will go through. Probably fine for reversible digital goods, but not much else.

Just knowing it's in your mempool isn't a very strong guarantee that the payment will go through. Probably fine for reversible digital goods, but not much else. Some systems pay miners to look at their block templates to get a better assurance it will confirm (and that it won't be replaced), but it's still not very good, and given that Lightning is now running on mainnet there's little value in continuing in that direction.