Use the search function to read up on this before you invest. Many members have switched back from K&N because of fouling the MAF. Others still swear by them though.
Yah, I'm not a big fan of changing out the plugs either ... unless there is a problem. In the Samurai I had years ago, I never changed the plugs & at 225K miles, it started running really bad. I pulled the plugs & found that although they were in pretty good shape, the gap was about 60 (twice what it should have been). The replacement plugs lasted about 20K miles. I regapped the original plugs & put them back in for the remaining 50K miles that I had it.
On the other hand ... with electronic ignition, bad plugs CAN cause upstream problems if left in too long. Basically, if the plug is bad enough, the coil can stay charged up all the time & never get discharged. Coils don't like that.