I hear you. I enquired with Bass Gear Direct here in Australia about an NV610 being put back into production only a month or so ago. He said he believed they may be doing a limited run later this year - not sure if he meant the NV610 or NV610T and not sure how accurate his info was. In the meantime he was steering me towards an NV412 - read up on forums here about the 412 v 610.
A week later the guy from Bass Gear Direct messaged me out of the blue, telling me of a second hand NV610 available on an Australian Bass Forum. (How cool is that ? A retailer happily losing a potential NV412T sale by directing me to a secondhand cab. I will be buying something else from them in the future) I luckily acquired it, and had it a couple of weeks now. it's everything that everyone said it was going to be, paired with my Heritage SVT.
So, I guess my point is, hang on, or make some enquiries and see if the rumour about the NV610 run I was told may have some truth to it.
I was unable to try one before buying, but I can suggest you should buy with confidence.
Nice, post some sound clips!
I'd prefer the NV610 and not the ported version but I am sure it still slays.