How would I reply to one who says that salafi’s believe that they are the only saved sect ?

I say in reply:

This accusation is indeed a huge accusation against the salafis and it is untrue. Those who say this do not understand the hadeeth the salafis are referring to and they give their own interpretation to it also which is extremely dangerous and is the cause of division in the ummah. If only they would resort to restricting their understanding of the quran and hadeeth to the sahaba and first three generation.
The hadeeth in question where they derive their false accusations from is this:
The Messenger of Allaah (s) said: “My ummah will divide into 73 sects, all of them in the hellfire except one. He was asked, “Which one is that, O Messenger of Allaah?” He (s) said: That which I and my companions are upon.” [Abu Dawud, Ibn Maajah, Ahmad, Ad-Daaramee]

So anyone who strives to be of that one group will be of those saved on the day of judgement and enter paradise. the problem these people have is in the answer the prophet (s) gave when he described who these saved group will be, he said: “those who follow that which i and my companions are upon”
So salafis strive hard to follow what the messenger is upon and his companions where upon from dress to character to fiqhe and ageedah and sunnah. When they do this and call to this they encounter other muslims who do not accept the interpretation of the sahaba and want to stick to their desires and emotions and modern interpretations so they speak ill of the salafi trying to put others off what the salafi is calling to. they do this by saying : “oh you think you are the saved sect and everyone else is in the fire” this type of rheteric will put anyone off salafis and what they are calling to. especially when the salafi is always quoting the saved sect hadeeth intending to save others by it and bring them to the saved sect! those who have deseases in thier hearts twist this to make out the salafi is saying he is saved and anyone else is in the fire.

Pay no attention to this false accusation and lie agains the salafis it is untrue.
after saying that… i must say that in the past and present their are and were some salafis whos manners and characters have been terrible and they could have led other muslims to understand that is what they are saying ie they are saved everyone else is in the fire – so salafis should reflect on thier behaviour and the way they speak and not be over zealous to guide people to their way. they should just relay the message in the best way and hope Allah guides their hearts. Allah says: “you are not a controller over them” and he taala said: there is nothing upon you except to relate this great message” and he also said: “…do you become overwhelmed when they do not follow you..” so salafis must be a better example of the blessings Allah has bestowed on them of guidance.

Having said that, being upon the way of the salaf being part of that saved sect, following the messenger and his companions does not guarantee we will not enter the fire due to our sins. we may enter the fire due to our sins !
so no doubt there is only one saved sect…and that is the way of the salaf…i emphasis it is a way not a group or organisation. anyone can follow this way it is not specific to one set of muslims and not others it is the way of the prophet (s)