I do not purchase actual cages. We bought hog panels from Tractor Supply and hubby cuts and forms them into cages for me. Not cheap but almost indestructible and they do not rust.

20180509_135345 by Brownrexx, on Flickr

In my mind-- this is a question that has no clear cut answer.
  If you were to ask a professional greenhouse grower. They are going to tell you pruning and making plants run high upon a wire is the only way. But those growers HAVE to use that method. Because the only open empty space they have, is above their heads. A person with a sizable area to grow plants outside, might let them grow and sprawl out lower to the ground in cages. I've tried both philosophies, and saw advantages in each. But because of my larger ground space outside-- I grow in cages. I only prune as a method of blight prevention.
Here is another philosophy that has no clear cut answer. As a young man, an old deacon at my church grew only 6 tomato plants a year. He had enough space to grow 360 plants. He averaged over 80 pounds of maters per each single plant. Something I found hard to believe. His argument was-- why would I want more plants? I had him to show me his method. He dug a huge hole out in new virgin ground at a different location for each individual plant. No plant was within 20 foot of another plant. Every year those plants got a different location. He traveled 90 minutes to one certain place, to buy bags of cow manure, and the special potting he wanted. That is what went in those holes. He built special confinement cages that were so large, they had to be dismantled to move. 
TO MAKE IT SHORT-- He put more money and effort in those 6 plants, than I did in 50. But he harvested as many maters as me. Growing tomatoes isn't a "one size fit all" subject.

[mention]TomHillbilly[/mention] sounds like some interesting sage advice

brownrexx wrote: ↑Wed Jan 20, 2021 12:32 pm I do not purchase actual cages. We bought hog panels from Tractor Supply and hubby cuts and forms them into cages for me.

Oops, my mistake. Do you recall how much you pay for the panels?

[mention]ponyexpress[/mention] no, I am sorry I don't remember the price but I have not made any in about 3 years. I think that each panel makes 2 cages and I used the leftover flat pieces to make trellises for acorn squash.

There are both cattle panels and hog panels but the openings are different sizes. I think that mine are hog panels. Both are made of galvanized steel and do not rust. They are very heavy and strong.

ponyexpress wrote: ↑Wed Jan 20, 2021 4:47 pm

brownrexx wrote: ↑Wed Jan 20, 2021 12:32 pm I do not purchase actual cages. We bought hog panels from Tractor Supply and hubby cuts and forms them into cages for me.

Oops, my mistake. Do you recall how much you pay for the panels?

I use cattle panels to make arched trellises for beans. Ten years go they were about $17. They slowly increased a dollar every few years, but stabilized at $21 for the last three years or so. Now this year, like everything garden related, cattle panels have jumped to $26.

For tomato cages, I use CRW, rebar and pvc fittings.

[mention]ponyexpress[/mention] I am so sorry. I just Googled the hog and cattle panels and it turns out that I am using cattle panels. The hog panels have smaller openings on the bottom half of the panel. They would also work as cages but I like all of the openings to be the same size.

I bought them from my local family owned farm and home store but Tractor Supply does sell them also.

I don't have a large garden and want more variety, so I single stem my plants and plant close together.

I use a cheap greenhouse frame that doesn't have a cover on it and tie up strings for each plant.