There are two basic requirement of an air filter. One is to provide unrestricted air flow, and the other is to remove dirt. They tend not to be mutually exclusive, as the finer the filter the more pressure drop. Also as a filter starts to plug air flow goes down, but filter efficiency (particle removal) likely goes up.
There are some test results posted at the Bob is the Oil Guy
site, which suggest K&N filters (cotton fiber) tend to pass more air, but collect less dirt than a paper filter (Fram, OEM, and many others). So if you want ultimate air flow when the filter starts to get dirty, then the K&M might provide some very slight advantage. But, it may be at the price of poorer air filtration. Air flow at very high engine output levels might affect engine HP. However, with clean or reasonably clean filters it is likely to be insignificant.
Does the air filter restriction or plugging cause fuel economy to suffer? Tests done by the Oakridge National Laboratory
indicated there is a loss of fuel economy on older vehicles that use a carburetor. However, newer vehicles with fuel injection and closed loop combustion control, do not lose fuel economy as the filter plugs. This is because the control system adjusts for the air flow and keep the mixture ideal. They in fact found that the clogged filter itself collapsed from the pressure on it before there was any significant effect on fuel economy.
1. Fuel economy is not a filter issue with the Camry or Camry Hybrid
2. Engine protection is likely better with a paper filter of the OEM type or many quality replacements like Fram and the like.
3. HP loss if you replace the filter as recommended is an insignificant issue.
4. It is just a person opinion, but I think you likely can get get more efficient dirt removal with a lightly oiled paper filter than a non oiled. Some offer it.
5. Just me, but I can't see myself cleaning the filter and reusing it. Seems like a pain in the butt if you follow K&N's elaborate procedure.
Just my thoughts. I will likely stick with the OEM air filter if it is a reasonable price. The Toyota (Denso) oil filter is priced well, and also based on some filter area comparisons
it is very good quality. Much more area than a Pure 1. Seems to me if you are going to go 10,000 miles on an oil change, you want lots of area.