RQN value for Quantseq experiment

Hi guys,

I read some conflicting results about the minimum RQN value in Quantseq experiments.
What minimal RQN value is acceptable for a human Quantseq experiment?

Moreover, is it possible if the majority of the samples have a RQN value > 7, and some samples have a RQN value <7 to include RQN as covariate in your model to retain the information that is available in those samples?