We were full time for almost two years and will be again after family issues resolve. We were RV newbies and I agonized over the choices. We love the rear bath and the twin beds that allow us to carry myriad people without making strangers sleep in the same bed. We manage fine with the space though if our granddaughter travels long term with us, it will probably feel tight. There are trade offs no matter what. For us, the final deciding factor was the payload. Add the extra weight and extra slide of the longer rigs and you lose about 1000 pounds of payload. The 2552 has about 3k to start with depending on options chosen. The longer ones have about 2k. I calculated the weight of water, gasoline, propane, people, pets, food, clothing, tools, toys, kitchen gear, outdoor gear, office equipment (we were working from the road), and just general "stuff" and quickly locked in on the 2552. We tow a Subaru Forester with a car top carrier and it acts as our extra gear wagon as well as our transport shuttle. We don't load the inside of the car too much because, again, we want to be able to carry extra people to the store, dinner out or just to a remote hiking or biking trail.
Ron, those blow outs are frequently due to overloading. I know a snowbird couple with a fifth wheel that blow out tires damaging their rig just about EVERY year. When they told me the story and I saw how much stuff they hauled I asked what their weight limits were and they had no clue. I can pretty much guarantee the weight they hauled was way over what those tires could handle.
Another note, the rear tire was dropped to qualify for some Ford specification for the extended frames. I assume it has to do with weight balancing but I don't know the specifics and can't speak on that. By dropping that spare tire, the Phoenix will get some "blessing" from Ford they didn't have before. I further assume competition has it and touts it so you may be able to find a reference and figure out the specifics by checking claims that way if you so desire.