Is there a long-term committment or contract?

No, you can choose to cancel your subscription at anytime. There are no long-term contracts or commitments at all and right now you can secure access to an 'Early Adopter' account with zero monthly fees ever, you'll get a lifetime account without any limitations.

Please be aware that as soon as you cancel your account, your tests will also be cancelled and you will no longer have access to them or the statistics