In their favor:
As homeowners and landlords they should be more reasonable and take better care of the place.
Steady income with SSI and willing to hustle when they need more.
They are motivated to make it work, offering more and reasonable concessions.
If there is no carpet there would be less impact by dog or bed bugs, if either go worst case scenario.
Not in their favor:
They may be renting as a temporary situation until they can find where they really want to live long term, so they may not be a long term tenant.
They are not familiar with the neighborhood, other than school district quality, so they may not be a long term tenant.
What I would look at more:
How long have they all lived at previous addresses?
Is there a reason they are willing to be so accommodating to get this property, is everyone turning them down.
Can the concession be a combo of pulling payments forward and paying higher rent, like pet rent.
I would say stick to your gut and your criteria, but consider the gray areas to see if any criteria or reactions need adjustment.