Even in the US there's a lot of good reasons to go through your insurance. Your insurance is the one contracted to work in your interest; the other party's is not.By the way, why is YOUR insurance involved? If the other party is at fault, normally (at least in the US) the other party’s insurance should handle everything.
In this case with multiple vehicles involved? Go through your own 100% instead of waiting for the other parties' insurances to figure out faults, limits, percentages.
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