We have been testing their service for around 2 months. Initially this deal made us really excited as they were claiming to do some great stuff that the others were not offering. Cleaning up catch-all emails was one of them and it was one of the biggest reasons we purchased this deal. But that is a totally false claim.

The catch-all verifier is mostly a joke. Probably around 5% catch-all emails can get verified by their system with low accuracy. They still mark the other 95% as catch-all. Catch-all email verification is not easy, we all can understand that. But the way they were highlighting it made a lot of buyers believing and purchasing the deal only for that. Try verifying "support@appsumo.com" which is a valid email (they marks it as risky).

Temporary email verification is also not good. It can detect many older temporary emails, but cannot detect most of the latest temporary emails. Real spammers are not gonna use old temporary emails! So not much helpful.

Verification accuracy is not so good. They mark a higher number of emails as good, which is true. But we are also getting a higher number of hard bounces. They say on their homepage, "Other verifier ~50% deliverable, mailverify ~80% deliverable". But they won't tell you that you will probably get additional 50% bounces from that additional 30% (enough to kill your domain's reputation). It seems like they are not verifying all the parameters before marking an email as good to some some money here. This is a very bad practice. We do need higher number of good emails, but not at the cost of accuracy (higher bounces).

They cannot detect spamtrap emails at all. Our system got hit by many spamtraps in last 2 months. So, we won't rely on that either. Last week we tested it with 200 known spamtraps and the system marked about 14% of them as undeliverable and not a single one got marked as spamtrap.

Are there anything good about them? Yes, there are. The UI design is great. It's easy to understand the layout and it also looks great. Overall verification speed is good, no complaint on that. The credit limit is also good. The credit renews on time smoothly. Have not tested their API, but will probably work the same way.

If you are happy with extra bounces or just want to do an initial checkup, you can get the deal. However, if accuracy and low bounces are your first priority, then this deal is not for you. I will update my review if the situation changes in the future.