I’m sure you have compared features but the information and comparison charts in link may help further. I would select the one that meets your most important needs and if it’s the subzero, decide if those particular features are worth the $5,000 https://blog.yaleappliance.com/the-5-best-integrated-refrigerators

I have a 36” over/under SZ. I absolutely love it, but honestly, I got it at a great price right when they redesigned the model. You’re going to have a fantastic fridge either way.

We were early adopters of Thermador fully integrated columns around 12 years ago. Still happy with the choice. They perform well, with separate compressors, good cooling, and solid ergonomics. Back then, SZ did not offer a fully integrated option, so the choice was pretty simple. Only issue we've had is with the icemaker--it's been replaced twice. Some of that is inherent to any mechanical icemaker, but it's worth a mention. FWIW, the 17 year old SZ we have at the lake has a lousy icemaker--ice freezes up at the top of the bucket, preventing it from dropping down on the auger, and requiring me to pull the bucket out and either discard the (freezer burned) ice, or at least bash it to get it to fall down. We have a Scotsman ice maker, which mitigates the problem.

In the end, it's an imponderable: take the chance on the Therms, which I believe provide comparable performance, or pay a lot more for the perceived greater reliability of the SZ (which I think is in part urban legend rather than proven statistical analysis).

I am having a similar debate here. Option to get a floor model SZ french door 36” in Stainless Steel on sale for about the same price as a Thermador 36” French Door with custom panels (with the rebated hood). The custom paneled Thermador fridge would obviously look better any day but will the awkward door containers and high shelving make me regret it? And why can‘ t I seem to find any Thermador owners? All the people around here that buy into the more expensive fridges sing the SZ praises so maybe I should take the SZ floor model deal in SS and run? Thoughts?

I've owned 2 SZ refrigerators and never had a problem. My parents had their SZ side-by-side for 25 years before it needed a repair. It's still going strong.

I think @Maureen gave great advice.

My SZ side-by-side is still going strong at 28 years old, though its very longevity begs the question: are the currently manufactured SZs as high quality as those manufactured years ago? Will they be as reliable? I schedule a maintenance/cleaning service call every 18 months, and keep my fingers crossed!

Yep. Our current sub zero is 27 years old!

Can you tell me a little more about the maintenance requirements as I have had two KA side by sides and never did a thing except a vacuum and water filter changes. What kind of cleaning service is required?

Went with the Subzero. Done!

I've had all three, Sub-Zero, twice, Thermador, once, and KitchenAid, twice. They are all good. Currently I have a 20-year old KA 48" refrigerator/freezer and a 7-year old KA 36" Architect II French Door garage fridge. The Sub-Zero's were 20 years-old, both sets when I got them. They are still running well. I did have to replace a compressor in one of the freezers. They were indestructible. Jury is still out with the Thermador columns. But, the new owner isn't complaining about them. While I expect great performance from the Sub-Zero, the KitchenAid's are a pleasant surprise. I like them all.