bag comparison (roller bag vs. backpack)

I know, everyone's least favorite topic. I'm leaning very heavily towards the farpoint 40 (or the fairview 40) - it was by FAR the most comfortable bag even though the REI Trail 40 looks more compact. (I'd love a Minaal but not dropping $300 right now...). Anyway! We'll be traveling for 2 weeks, on a mix of budget airlines and regular ones, and I'm torn between the backpack (for the usual packpack reasons), or the Maxlite 4 Rolling Tote, which is smaller and easy to roll around.

We'll be in a mix of places - small staircases (points for backpack), lots of airport walking (point for rollerbag).

How have you made the decision? I'd have an easier time if I loved the bag, but the fairview/farpoint aren't bags I can really use for work, and can't use for hiking, so it's definitely less multi-functional...but boy would it make this trip easy. Would love anyone's input!