We have used Allianz before for travel medical. Through our extended health with Green Shield, we get two weeks travel medical included in our premiums. We have purchased top up to allow for 30 days. You do have to complete a medical questionnaire if you are over either 65 or 70 (believe 70). Everything was fast. I am now looking at our next holiday and need to add cancellation/interruption.
We will be travelling on a Celebrity Cruise but there insurance didn't seem to cover everything. Seeing posts here about Princess, I will re-look.