Hi, my brother is trying to get a pardon for a crime he did in the past. 9 years ago.

He is getting married and his girlfriend wants to go to the states after marriage. So now he is going to visit a law firm that provides pardon service for Canadians. But from what we heard it will take a long time.
Has anyone here ever had an experience travelling with a pardon? He is getting the Pardon to be allowed into the US, but how will this work when he travels internationally? I mean like at crossings, will it cause him any hardship?

Some friends told about the US Waiver scheme. And suggested some criminal law firms in Toronto. Is it better than the regular pardon? And how much will it cost? I'm fairly ignorant about the pardon service. So please help me with this.