I have heard it both ways. I have seen one company say that the radio makers claim you need to use their crystals because they want to sell you their own brand at heavy markups.
I have read that you should use a matched pair from one manufacture. I have seen it said you should use the brand of the tranmitter. I have receiver which insists it will only work if you use crystals from them.
Does anyone have real information on whether there are real differences.