I really liked Fox idle bar plugs in my Enya 4-strokes. They outperformed OS F plugs in idle speed/quality and top end power. And they're half the price of OS plugs. Some of my hobby shops have them hanging on the shelf. One shop has a bunch of miracle plugs on the shelf priced around $7 each. I really like Enya and McCoy plugs, but Picco and Merlin plugs are stellar as well. I have found the engines hat people typically use idle bar plugs in (baffle piston engines) run spectacular on Enya 3 plugs. They are one of my favorite plugs.