Upgrade Router OS 7 on RB850Gx2

RouterOS
1

I have RB850Gx2. I install Router OS 6, version 6.49.19 (long-term). I use RB850Gx2 as backup.

Should i upgrade to Router OS 7, version 7.20.8 (long-term) or version 7.22.1 (stable)?

2

What is your use case?

Is this production/lab?

Do you have physical access to the device?

3
  1. Before i use RB450Gx4, i use RB850Gx2 for production. Right now, RB850Gx2 use for lab, and also that router for backup if my RB450Gx4 has failure.
  2. Before switch to RB450Gx4, yes, it has so many physical devices, such as switch managed, and 3 APs.