I have bought and sold safely.
The real problem is customer service : you never get to talk to anyone, and they just do not give a s*** and reply with template emails. If everything goes smooth then ok. But the moment you have a problem with the parcel or the purchase you won't get ANY help. So, why are the buyers paying the service commission?
I lately had a very bad exoerience, thry literally STOLE 20 euros, so I won't be recommending to anyone anymore.