We wear the waist pack type of manual inflatables, except at night or in rough conditions we wear a full vest type with integral harness.
The waist packs are comfortable enough to forget about them. One day when driving home after a day sail, my wife (who was at the wheel) suddenly screamed as she got out of the car... she forgot to remove the waist pack and the rip-cord had snagged on the seatbelt: When she got out the PDF inflated with a loud WHOOSH and startled her. We had a good laugh.