I don't know the track history of the Autozone DISs. But, you probably know that Azone doesn't actually make parts, just takes bids from and then buys bulk lots from suppliers. So an Azone DIS might actually be made by Wells or Borg-Warner, or some other company at any given time. This is one of the reasons that Azone has a reputation as a low grade or marginal quality parts provider.
I suspect that if you have a cheap one from there, then it might be the problem. If you have an old one that was working sort of OK, you might try using it to see if the problem goes away at least temporarily.
IMO, heat extraction is not the biggest reason for DIS failures. It certainly doesn't hurt and can only help extend the life of the part, but the OEM part can go for years w/o a problem in the stock location on the A/C bracket.
Do you know the brand(s) of your Azone DISs so that we can avoid buying them?