Been running after market intakes and filters since new, and my MAF is fine. After many a filter oil bath... cleaning it is a regular necessity. Every oil change.
Now regarding your problem. Although it is likely the MAFS, given the sensitivity to corrosion (exhaust gas recirculation), it could be a leak in the intake... behind the MAF - 'Unmetered Air'.
If you have a leak down stream from the MAFS this could cause the same code. Since there needs to be a vaccuum in order for it to suck unmetered air in, it'll be between the MAFS and the turbo inlet.
To find it, beyond the obvious visual inspection, if you can find a source (welding shop), you use compressed nitrogen to 'soak' local portions of your intake with the nitrogen (spraying specific areas) while the engine is idling. If the portion of the intake you are 'coating' in Nitrogen has a leak, it will suck it in and make the engine stumble.
The only difficulty with this is your intake. You may have to remove the filter and rig a new intake tube such that the car is sourcing are from outside the engine bay. That way you won't mistakenly fill the actual intake path with nitrogen and get a 'false positive'.