Gap year study abroad/exchange before Canadian Med — GPA impact & school policies?

I’m currently considering doing an exchange program abroad during  my last year while applying to Canadian medical schools.

Before committing, I want to make sure I’m not accidentally hurting my application. A few questions for anyone who has done this or knows the policies:

1. How do Canadian schools treat exchange grades if exchange is in the US?
2. Is it worth it? For those who did an exchange, did it help your application/MMI responses, or was it a logistical headache?