Well, first of all - my opinion - they are very good...with solid software and a good set of features...so hold them.
I don't know what is their average lifespan...and I don't mean the Hardware lifespan...but how long the HPE/Aruba will continue to support those specific Comware based series (which isn't actually part of what is offered for DC deployments requiring specifically Comware NOS based switches)...they are almost at least 5 years old (2014, first QuickSpecs here)...my take is that they will continue to be supported and, eventually, once a EoS date in the future will be defined and released to the public you still have some years during which you could expect some software updates (security fixes, mostly) before EoS date is finally reached.