Thats a very reasonable point, specially considering the $100 difference in price.
But, even after all this questioning and learning, something is still unclear to me:
Is the AC88U actually "better" than the AC68U?
If I test the AC68U and AC88U in the exact same place, with exctly same devices, exact same placements, and exact same ISP bandwith conditions (fantasyland), would I actually find results showing at least a "marginally" better signal performance at far distant placed devices (ipad, macbook, gaming console, etc) on the AC88U than on the AC68U, OR can I expect the exact same performance or even worse??
Believe it or not, I still dont understand if there will be an improvement (even if only 2%!) on that area if upgrade to the AC88U. If the answer is "yes", even if only slightly better, the upgrade makes sense to me.
If the improvement is in other areas of the router performance (faster USB, faster VPN, etc), which I dont need, it makes no sense and I will stick to a second AC68U (or P).