I am. I'm at $86/month for grandfathered unlimited data, unlimited text and 400 minutes a month (that I don't use) after the FAN. And I think that's about to go up $5/month, right? so $91 (with tax) to ~$98? 7 dollars to add tethering? Sure, why not? And I think they'll eventually turn FAN back on for these plans.
I was doing basically the identical w/ 450 minutes that roll over and the roll over minutes always covered, the $5 hike is definitely coming and another after that, tethering at LTE speeds is the best, will save me on my next iPad Pro, no need for data and the more expensive model