Full timing isn't for everyone. That said, it offers a freedom unlike anything I had ever experienced in my adult life. I would simply offer the advice of looking at
RV Consumer Group. They rate new and used RVs with regards to safety, economy, and reliability. Some folks don't place much stock in their evaluations. The fact that they've been around for 20+ years is a testament that many find value in their information. It does cost to acquire that information, as they receive no funding from advertisement in the RV industry. But, it's a pittance relative to the overall investment you will be considering.
As an aside; New Horizon and DRV are probably considered "top-of-the-heep" full time 5th wheel manufacturers today due to their offering of semi-custom work and quality. A little lower tier would include Excel, NuWa, Carriage (orphan), and Travel Supreme (orphan), to name a few. Teton, also an orphan, would fit in there as well. Those manufacturers have enjoyed a reasonably good reputation over the years and have been popular amongst full timers. A gently used unit will cost less than new. All will require a stout truck.
You might want to look at some full timer's journals or blogs for your edification. A good one to start with would be
RV-Dreams. The Payne's are pretty forthcoming in their lifestyle and expenses as full timers. Of course, yours can vary. Good luck. It's an exciting time for you.