No one can successfully predict the market right now, anything could happen. Bitcoin can survive and grow exponentially, Bitcoin Cash can surpass it and then grow much higher... They can both coexist with similar prices, or one much higher... There are so many different possible scenarios that i'd recommend either holding both as some kind of hedge against any outcome, or holding neither and wait out the storm (keep your investment in alts/eth/etc)
I agree with you market is unpredictable specially when you talk about bitcoin because its rate depend on users supply or demand in world.
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