As others have said, it really depends on you and how you use it.
Personally, I use Cellular on my iPad all the time - sometimes even over free Wifi (my LTE is generally faster).
Some of the disadvantages of a "hot spot" for me:
- You're depleting the battery of both the phone and the iPad. Again, this isn't bad if you don't use it often or for long periods of time.
- Connection time - you still have to go through the action of connecting to your phone. It may be only seconds, but it's still more than just taking out the iPad and doing what I want to do immediately. Add to that the extra time it takes when it "fails to connect" (which happens all too often).
- You can only use connected apps when it's connected to a hotspot (or WiFi). This seems like it would be obvious, but there are a lot of things the iPad can't do when it's off-line.
- Hot Spot Data - don't know about anybody else, but Verizon limits Unlimited HotSpot data to 10 GB (again, not a huge problem, especially for "light" iPad users - but if you use your hotspot for other devices, it can add up).
In the end, it all boils down to what you want to do with it. I would never want to use an iPad with a hot spot. Personally, I would rather have cellular connectivity on my iPad and no phone rather than trying to do a hotspot. When I travelled overseas, Verizon allowed me to use all of my regular LTE data at the cost of $10 per line, per day - so I chose to activate only the iPad data with cellular because it was more useful than the phone and trying to hotspot every time i wanted a connection.
Just a personal experience, but to me Hot Spots are only for people who might only want to use cellular data once or twice a month and are in the mindset of connecting (i.e. it's more than just checking mail or other "quick" data uses).
