I have not done this Replace by fee (RBF) but a friend of mine did it and told me that it was good and it made the transaction very fast. Really not everyone knows how to accelerate their transactions. In my own understand of the whole stuff is when the person uses low transaction fee with many blocks to verify the process, then the delay of unconfirmed occurred. But if the person set high transaction fee rate, then the transaction would be faster. When the transaction is slow as it is said, the person can check the mempool to track the movement of the coins.
Op thanks you for the information.
If you always do peer-to-peer transactions, I advise you to get used to using the feature. An example is that you buy bitcoin from someone you do not know and send you the transaction with a small fee after you pay it. Through the CPFP feature, you can resend the amount in a new transaction to another address of yours. This will cost more fees, but a more secure transaction because as long as the transaction is not confirmed by the network, the sender can recover the bitcoins through the double-spend feature.
The Bitcoin protocol provides useful features. All it takes is your seed words. Unfortunately, most users are not aware of this because closed source wallets and trading platforms do not provide these features on the wallets that they offer. I think they should not be called wallets at all.
Whenever I receive bitcoin from a stranger (which would be someone that either I do not trust or that I don't know their name or their address), so far I have always waited for at least one confirmation prior to giving over anything of value, such as cash.. so it is up to them if they pay a higher fee in order that they do not have to wait for the one confirmation.
Of course, if the transaction was for something that I considered to be great value, then I might wait anywhere between 3 and 6 confirmations... but most of the time, I have been o.k. with waiting for 1 confirmation, and I always disclose that before accepting payment in bitcoin.. and surely if the person was friend or a family member, then I would not need to worry about getting at least one confirmation before transferring the item of value (or money).
Maybe none of us are experts, so sometimes issues can end up coming up, and I have had some issues in the past when dealing with strangers in which mistakes had been made, and surely some people are more honest than other people in terms of correcting the mistake.. to the extent that the mistake had not either been intentional or that once the mistake had been discovered, then sometimes people might NOT end up doing "the right thing" in terms of rectifying the situation.