Rolex benefits - good fit & finish, high degree of build quality, (higher) resale value retained/gained over time, legal (not contraband)
Top quality rep benefits - relatively cheap, provides appearance of gen
Rolex negatives - expensive, costly to repair (especially, in the case of vintage)
Top quality rep negatives - little or no Q/C, unreliable until/unless professionally overhauled, legal issues with ownership in some countries, low resale value, risk of being identified as 'poser'