Yes. We do have have free mail relay trial for 21 days but the relay is only limited to 20 relays/day and only works on server relaytrial.dnsexit.com. The trial is for our users to make sure the service works.
The free trail can be sign up at this address:
However, our mail relay service do have 30 day money back guarantee. If you are not happy about the service and not abusing the service, you can either contact us through Live Help, Support Phone, or email to firstname.lastname@example.org asking for full refund.