I used Uplead sometime in 2018. I'm adding this review based on my experience at that time. Overall it is a good experience, to find an affordable b2b contact database is such a big help for a freelancer like me.
Cons: The database wasn't as updated as I hope it was. For example, there was a lead that no longer has been working for Company A for 5 months but was still connected with Company A on Uplead's database.