I be done three f journey cruises and several b2b. I love them both and agree with much of the pros and cons listed with one major exception. I find the turn around day on b2b to be a pro. Its the only time you nearly have the whole ship to yourself. There is usually about 45 minutes that the ship is at "zero count" ( meaning everyone that needs to be off from the first sailing). The crew is busy getting things ready for that he first passengers to arrive and it is super pleasant.
Th recommend both