How long until you replace Quattro FX mask liner?

Not the pada-cheek stuff but the actual silicone part that is suppose to make face contact. I have a liner but it seems the mask is "wearing out", this part is over 50 bucks so how often should I replace it?

I have the Quattro, not the FX. I find that I have trouble getting a good seal at about 3 months. That's when I replace the seal. It may last longer, but I really do not clean the seal often.

I think they are supposed to last 6 months, but if you find it not sealing well I would do sooner.

You should get 3-6 months out of the QFX cushions. Ditto for the M.Quattro.
I wash my cushions less when using a liner, so that helps too, even though I use a VERY mild soap.
In any case, replace whenever necessary.

Medicare allows for replacement of the cushion once a month. As I remember it you just got insurance and the insurance will cover your supplies??? You might want to check w/the local DME provider(s) they are contracted with how often your insurance will cover the cost of a mask cushion. But it would also be worthwhile to ask your insurance how often they will replace the mask cushion as it can vary from one insurance to another. AND BE AWARE many local DME providers don't want to be bothered carrying extra mask cushions and various other mask parts so they would have to special order them for you which takes time.