Hey there,
Here's my 2 cents worth from a Reflection 5th wheel owner....short lived, but here are my observations.
Build quality: very nice. Nothing is perfect, and I only had a few warranty issues that were sorted quickly. Impressions of when we picked it up were very good. No piles of sawdust in cabinets etc, no stripped cabinet screws. Very nice. It's not your first rodeo, so I'm sure you realize that "experiences may vary" when it comes to RV's. :)
As for your floorplans and intended use I would only suggest the 315RLTS.
You want as much room as you can get. The front bedroom with slide will offer WAY more comfort in terms of space when shuffling around getting dressed etc. Plus, the washer and dryer preps are what you're going to want too.
My 5th was a 29RS which is similar to the 297RSTS. We got it because of the outside kitchen, which is very nice. Having said that though, that means that your "living slide" is now in full view of your neighbours, and you also lose any views into your own site. Might not seem like a big deal, but if you're going to be set up for lengths at a time, it might be nicer to have your neighbours 'blocked' by the inside entertainment slide like the 315 has. In hindsight, it would have been easy enough to create our own outside kitchen with the folding table we travel with by simply putting a TV on it and small fridge/electric cooler underneath. To be honest, the TV was used once, and that was when we were set up on our permanent site.
Now, the 315 is a gigantic travel trailer, so you will know it's behind you. I borrowed my BIL's 38 foot trailer a few summers ago and pulled it with our '14 Ram 3500 CTD. No issues with power, but it is definitely a long sail behind you. Nothing scary, but definitely noticeable. Go big truck :)
They are nice solid, heavy trailers. Well insulated, and make sure you get dual pane windows. We camped in freezing temps and woke up to very little condensation on the windows. For longer term living I'd suggest a small dehumidifier as well to keep the moisture down.
Sounds like you have a great plan.
If you have any pointed questions, or if I've left anything out in my ramblings here, just PM me :)
Mike