1 ARDR is currently worth 3.7 NXT on the built-in fully decentralized asset exchange:
https://nxtportal.org/assets/12422608354438203866
Risk of the decentralized exchange goxxing you, insider trading against you is ZERO.
To trade you need a NXT client https://nxtforum.org/nrs-releases/nrs-v1-11-2/