Have owned three types, pipercross on my astra coupe, green and K&N on the VRS and have had NO problems with any of them.
The pipercross does not need any oil as is foam based, the green one was in and out within a few weeks as I thought it was naff, brought the K&N one to replace it and felt a difference straight away.
Yes the K&N filter does need oiling but unless you are a complete retard and put the filter back in dripping wet it wont cause any issues, had mine 2+ yrs and nothing, just follow the instructions and dont think more oil is better!!!
I would say if you were worried about doing this incorrectly then a foam filter would be better (however they still need cleaning so dont put it back in wet!!).
Would not bother with any forced air kits like viper, BMC etc personally as they are very expensive and the rolling roads I have witnessed especially with the Viper type produced less Hp than standard!