The closest we got to Conakry was Mamou. We were told the road from Mamou to Conakry was all good though.
No info on Conakry to Freetown but I overheard a group say it was fine now.
From Faranah and eastwards, there were no obvious good roads going south, so you may want to stick to crossing over from the Conakry end.
Actually with public transport, your chances are better since you can easily abandon your vehicle and hop on another one (if you travelling light enough).
At some really bad spots, you will likely get vehicles operating after the obstruction, not an option when with your car/bike/truck. And if your vehicle gets stuck, you may also join another
Port Harcourt, Nigeria