It's all a matter of preference.
You said you were missing left...the question that needs to be answered is why. Is it a targeting problem or is it because the ball is hooking past it?
If you're having problems getting your strike ball to go straight on a consistent basis, a plastic spare ball will go a long way toward eliminating that problem.
If you're pulling the ball off your target line, maybe you need to work on hitting your mark better.
In my case, it was a matter of not being able to consistently kill the roll. If I did, I made the spare, but more than likely, the ball would hook just enough to miss. A plastic ball improved my 7 pin % from less than 40% to well over 75%. As a result, my average is up by at least 10 pins.
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Unless, you were harmed. In the extremely rare case were that to happen, Tough Nouggies!!!
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