Wonder why you think it may go bad. The PD series of converters are one of the best in the business. My trailer has a 9100 series converter to which I added the Charge Wizard way back in 2004 when we purchased it new. It has run almost continuously since then and shows no signs of giving up. If it does, it would be an easy swap out for a new one.
I don't think I would worry about it conking out on you while you are on a trip. If, by chance, it does then you should be able to get another one fairly easily.
I would not replace it just because it is getting older.
Barney