How often do you replace your gear?

I just passed the 3 month mark. I called my medical supply company and they sent me a new mask and heated hose. That seems pretty quick to replace stuff that Is working fine. So how often do you guys replace functional equipment?

About all I can say is that my mask and heated hose is a little over 2 years old. My wife's heated hose is probably 4-5 years old. I have replaced the nasal pillow insert in my mask a few months ago. I pay out of my pocket for what I use, and have no insurance.

Counting the original mask and hose I have had 2 heated hoses, 3 masks and 2 pillow inserts in 6 years.

So I guess that makes an average of every two years.

As with Sierra I have to buy my gear and I do resent spending money on something that I really abhor.