A: Looking at their deal terms, they have a 600M database with 1000 credits for $49
Leadrocks right now is a 130M+ database with 5000 credits for $79 (or 7500 for $89 on a Plus Exclusive deal).
The ultimate decision is, I think, up to the customer, whether or not either of those tools work for the customer profile they're trying to reach out to :)