While we also don't have pre-existing conditions I have found that the medical has served me well.
My mom was scheduled to go on a cruise and my grandmother fell ill the day she was to leave. She was reimbursed in full for airfare and cruise fare. On our
DCL trip this past April, my husband ended up in the medical facility for a respiratory infection. I submitted it to my personal health insurance and they put a portion of it to my deductible, but the remainder was deemed out of network. I submitted to
travel insurance and they reimbursed me the full amount I paid.
Also, don't forget that it also includes emergency evacuation (usually up to $1,000,000) if you need to use med evacuation. Most health insurance won't cover that. So, while you may not think you'll ever need the medical portion of it, I would feel much safer with it!
I just don't pay for it until I've made final payment because we don't have pre-existing conditions either.
Just make sure you read the policies and pick the one that will serve you the best. There are a lot of options out there but I wouldn't book a trip (especially out of the US) without it!