Does anyone own one?
My 2010 iMac is not getting any support for the three browsers that I use. macOS 10.13.6 High Sierra.
Safari, Chrome or Firefox. The computer works perfectly but without support I have to go from one browser to the other to find one that will do what I need. Sometimes video won't play on one while it will on another. Articles won't show on one while it will on another.

Anyway, I can get a good Imac with the M4 chip in it for around 1300 but the Imac Mini can be had for 599.
The mini is a small unit that you supply your own keyboard, mouse and display. The Imac comes fully ready to go and the mini seems to have more capability than the iMac I'm looking at.

I have the wireless mouse and keyboard already. The monitor I'll need can be anything from $60 to whatever I want to spend on it. They recommend 4k which starts around 145 but I'll probably do a wide screen 32" for a little over 200 bucks. The mini will also control up to 3 displays.

If anyone uses one, what do you see wrong with what I'm looking at?

I had an Imac mini and liked it while it worked, that was about 8 years ago. I liked being able to use the monitor of my choice, mouse etc...I did not get 6 months past the warranty be it crapped out and was not worth the $ to get it back up and running. From there I went to a panasonic toughbook laptop now use a Lenovo laptop. My daughter liked Macbook air but 2-3 years max and the cost to fix pushed her away from the Apple computers.

It's a good move to be more frugal. With a privatized Postal Service there could be some belt tightening in your work environment.

I’m on my third Mac mini.
From what I understand you don’t want to use a Mac that can’t get the updates. You are not protected from the threats the updates fix.
I like the like the Mac mini, the only reason I am on my third one was the issue you mentioned the previous two were no longer supported.

He's retired. But don't let facts get in the way of your lies.

It appears not a whole lot of people here own them.
I was going to replace it with a new Imac but the cost factor of the mini just makes that the common sense choice.

More food for thought – Many older iMacs featured 27" monitors, while the new iMacs come with smaller 24" screens. When I came to this crossroad, I found the new 24" iMac screen to be too small compared to my 27" iMac.

If a larger screen is important to you and you're already considering a 32" monitor, the Mac Mini might be the better choice. Pairing it with a refurbished 27" Apple monitor could retain the aesthetic appeal of an iMac, though this option is likely more expensive than either the 32" monitor or a new iMac. However, you'd gain the benefit of a larger Apple display.

While your 2010 iMac will never match the Mini’s performance, you can still upgrade it or repurpose it for other uses—like a secondary monitor (via Target Display Mode) or as a media server for movies and music. A major advantage of the Mac Mini is its improved performance, long-term security support, and longevity.

Hardware and Software Upgrade Options

• Upgrade the iMac's Hardware - Replacing the hard drive with an SSD and upgrading the RAM (up to 16GB) can significantly improve its performance. However, this may not resolve software and browser compatibility issues entirely, and the new Mini is still a better long-term investment.
• Use a Lightweight, Modern Browser - Browsers like Arctic Fox, Pale Moon, or InterWeb are designed for older Macs. While not perfect, they’re more compatible with modern websites than outdated versions of Safari, Chrome, or Firefox. Unfortunately - Arctic Fox often has issues with High Sierra
• Hack the 2010 iMac to Install a newer macOS - With OpenCore Legacy Patcher, you can install modern macOS versions like Big Sur, Monterey, or even Ventura. This unlocks access to updated software, security patches, and a better browsing experience.

If I were in your position, I’d recommend going with the Mac Mini and a larger monitor. It’s a future-proof solution that offers the best performance, compatibility, and longevity for your budget.

First and last Apple Pc I've used was an Apple IIe or something like that. Horrible experience and never tried them again.