iZotope has a good sale/crossgrade on RX right now on all the usual sites. Upgrade to RX6 with a free upgrade to RX7 and a good crossgrade to RX Advanced as well.
What is the current state of RX and the current version of Nuendo? I know there has been a couple of audio ninja workarounds have been issued as the problem has been wrestled with. But has the issue been fixed so RX performs as it should as a plugin with Nuendo without the major gyrations and sprinkling of fairy dust?