For free? Take it.
Then ensure you run health diagnostics (many free programs for this, each HDD vendor offers there own) and see how it's health stacks up.
Only if it checks out as 'healthy' would I use it to store any data I couldn't afford to lose.
5 years old does not make it good or bad definitively. How often it's been used & any physical stress/damage are much bigger factors. 5 years/ 5 months / 5 days won't be any different as far as viability if it's been dropped repeatedly.