Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
I have unlimited data and unlimited hotspot on phone with business day hotspot battery life so the WIFI only version makes more sense.
 
is that an iPad data plan? Or you use your iPhone SIM?

I signed for the 200MB and they lasted 30 seconds... in my experience it's a gimmick
I think you use it wrong. The point is, the iPad always has internet. It's like cable vs. dial-up in the old days: with cable you're alway connected. When you pick it up, it has the latest emails, texts etc. You can write and receive emails, texts etc. You can check the web. If you need to do some heavy work, then you can tether.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.