John, I have read that cell antenna cable looses signal very quickly. If you're going to put your antenna on a pole, you might want to get a device that has the amplifier right at the antenna. Otherwise the loss on the cable could reduce the signal to less than a roof mounted antenna with a short cable.
I'm not expert at this stuff, but I bought a one-year subscription to https://www.rvmobileinternet.com/
They test equipment in real life and give suggestions for lots of situations. Before I read their stuff I had higher expectations, which turn out to be questionable. I've scaled back on my anticipated solution which will also save me $$$. This may sounds like an advert for them, but it's just a personal recommendation. I decided my annual fee would be money well spent if it saved me from a mistake. That had turned out to be the case.
I still have lots of time to decide, but I'll probably just get something like a cradle for my phone with a short cable to a roof mounted antenna. I'll use blutooth for calls and tethering for iPad/computer access.