If you want a high rate of fire setup that isn't going to explode on you, don't buy a cheap set.
You get what you pay for. High speed setups are more prone to breakages due to the high cyclic rate, which makes for more stress and more chances for errors.
Don't cheap out on the gearset. Want it to last, then get some SystemA or Prommy gears. Even modify if you are looking for something less expensive.
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