Yup, there is. I accidently proved this to myself years ago.

I had a K&B 3.5 cc outboard. I used to run it with nothing but K&B plugs. The group I raced with had disbanded so the boat sat on the shelf for a few years. One day I decided I would just bring it with me to the lake while I was out boating. Got it all cleaned up, installed a new plug (not K&B) and headed off to the lake. When I got it running I couldn't figure out why it was so much slower than before. No matter what I did, it just wouldn't unwind right. Not sure why I thought of it, but I pulled the (cheap) plug and installed the old K&B plug. Big difference. From that day forward I stopped buying cheap plugs.

I now only use OS #8 for 2 strokes, OS F for 4 strokes, and K&B on my boat and K&B aero engines.