The DIY air filter does not block up airflow.. in fact.. i I think it lets in more air...

I bought the first filter from the dealer.. the xB uses the same from the Echo.. it was 20 friggin bucks... so.. when i cleaned it after 20k miles (it was disgusting) I went with the DIY.. So far I've done my filter and my fiances on her 3.0 the day she brought it home......

I have enough left for one or two more... depends on how much i "not waste"

anyways.. i highly suggest EVERYONE do the DIY.. plus.. you can put stuff in between the filter to make the car smell good.... such as the sheets of stuff they sell at home depot that go in the AC for your house filters..... like a dryer sheet...