I know way less about VCM2 than Trav does, but I do know my very first purchase when we picked up a 2006 Odyssey from a family friend was the VCMTuner to disable the Eco mode.
There was definitely varnish present in the oil fill hole, but the PCV was still free at 135k. No clue how many times it had been replaced prior to our ownership.
Anyways, I put the van on a solid diet of PUP and alternated with A3/B4 oils on usually a 7.5k OCI and had good UOA, and a couple Kreen flushes mixed in for good measure. We put about 52k on the van in just under 2 years before I recently gave the van to my stepson and his family.
Because he's an extremely poor manager of money for maintenance and repairs, I have instructed him to use the Harvest King full synthetic 5w30 (which is d1G2) and change it on a hard 6 month/5k limit to try to avoid issues. It's got about 189k on it now, so I'll probably try to get some VC pics when it needs another timing belt around 200k.
I don't know offhand if VCM-2 can be disabled with something like VCMTuner, but if it can I would personally buy one ASAP. I only saw a minimal hit to mileage, maybe around a solid 1 mpg when averaged over a long road trip. It's obviously easier on the mounts, trans, and not driving you nuts as well by kicking on and off.