Those look like "six pallbearer" printers, meaning six weight lifters are needed to move them up and down stairs.
I have a "4-pallbearer," just an Epson 9900. It took a bit of effort to put it in place. After ten years, the head went and I was having anxiety attacks on replacing it with any one of several I found on eBay, a couple sounded good BUT. Called my service expert and he talked me out of it and I was relieved. He replaced the head a few days ago and it's back to cranking out the prints. I bought this printer second-hand for a large project of hundreds of large canvas prints. As the head was on its last leg I was able to coerce one last canvas run that more than paid for the head replacement. The 9900 more than paid for itself for the past decade and I'm the second owner.
On any second-hand printer, take a look under the hood, ask lots of questions and do some testing with your work before making the plunge. If you know a repair tech and can have them look, it may be worth the money for their expertise. Check the counters and any service records and if you know anyone with similar printers, ask them what to look for.
Also, find out the cost of the consumables to figure if this can be a good match. Though the costs per unit (ink) is lower with larger, usually, the cost of a cart can be a pucker-factor. That 44 inch printer may be the better of the two overall. Though solvent printers are great for signs including vinyl and canvas, they are a lot more costly at the git-go though I'm not certain how well they output for photography. If it's just 4-c, then that may limit the gamut for output and there's also the factor of the ink stability. Same story on the HP, if may be optimized for signs/plotting where color can be close but not the best. Research is your answer!
I found that 99.9% of my work could be done with a 44-inch printer though 90% of the time, 24" is enough. In years of large-format printing, I've farmed out only print that was too large and even in the last job, a 60x40 gallery wrap, I was just able with the 2" wrap to make it work.
If your budget is deep and you have the space, and the printers pan out (don't forget to see what's available for substrate, also!), I'd say go for it, but with open eyes. In my experience, it's paid off quite well.