Okay, I'll give it a shot, based on my limited knowledge on the subject. Major differences...first off built in fridges are often smaller in size to their free standing counterparts because of the cabinet design. That is why you'll see a lot of 42inch+ BI fridges. My SZ is quite a bit smaller when compared to my old freestanding Kenmore. Also, the fancier BI fridges come with multiple compression units/vacuum sealing functions, heavier insulation, and usually (which is a pretty important factor) a very solid warranty for years. Also, the price differences. There is a much much much larger market for free standing less expensive fridges. It would be safe to assume that for every built in fridge that is sold, the major players (Kenmore, Whirlpool, GE, Samsung) probably sell 10 or 20 units. Supply and demand is a huge factor. The major brand fridges also make their products overseas to keep the costs down. A SZ, Viking, or Northland fridge would be made in the USA and that adds a lot to their price. Also, the major built in manufacturers sell primarily to high end installations where people are throwing around $100,000 or more for a remodel. These companies have a brand image of being good quality and, more importantly, expensive, the SZ pro48 is like 16 grand. You take someone who knows high end kitchens and show them one with a sub-zero, viking range, and what not, and they will automatically assume the remodel was expensive. Compare that to walking into a house with a Kenmore freestanding, a GE range, and a Samsung microwave. That looks more "pedestrian" (I am not using that word as a put down by the way). I like to put it this way to people. Think about it like cars. Sure you can buy a Toyota Camry for 25,000, it'll run well, fit all the stuff you need, and get you from A to B for years to come. That is the best selling car on the road so you'll see a ton of them. Now imagine buying a car that does same thing, but paying $150,000 or more for it (think a Bentley or something). It will do the same thing as the Camry, but it'll be more powerful, handcrafted, and look incredible while doing it for years to come, and you'll rarely see one on the road. People will know it does pretty much functionally the same as any other car, but it has an image, and people will know it's expensive. All fridges do one thing, they keep your stuff cold. Some preserve food fresher for longer if they have vacuum sealing like SZ, and I can tell you from experience it DOES keep veggies/fruit fresher a lot longer than my basement fridge. Sometimes extending the shelf life of the food for a week or two more, sometimes even longer. Anyway I hope that this helps answer your question.

Extending the stiles refers to widening them. If your stiles are, say 2" wide each, you may have an option of widening them to, say 2 1/2" each. Therefore your 36" cabinet is now 37" as you've added a total of 1" to the total width. While this is an option, you will also need to consider that widening the stiles does not widen the cabinet box. When installing the cabinet between tall gables or tall gable and wall, you will need spacers to match the widened stiles or have the cabinet box flush with the outer edge of the stiles in order to attach the cabinet properly. Counter depth typically means it is closer the the 25" of the counter. It does not automatically mean it will work for a built in. Counter depth fridges are typically taller as well in order to keep the storage capacity. When it comes to building in the fridge, try to find a model where the doors hinge open in line with the fridge box width. If the doors hinge outside of the box, your doors will need to be proud of the tall gables on either side. Otherwise they will bind against the tall gables or, you will need a greater gap between the gables to accommodate the wider swing which will detract from the built in look you're trying to achieve. (Albeit crude, see below for what I'm talking about, top view)

We're a family of five. We eat lots of produce and I cook at least once a day. I bought a CD Electrolux all fridge a few years ago and don't regret it. The one thing it doesn't fit well is a box of those huge 16" take-and-bake pizzas. I have to remove them from the box or clear a shelf that doesn't have a door shelf across from it when closed. My produce may overflow the available space in my drawer for a day or two, but that's not really an issue. I really love that it doesn't intrude on my aisle because the fridge location in this house is stupid. FWIW, my fancy Gaggenau oven doesn't fit those pizzas, either. I have to cut them in half. I wouldn't trade my oven for one that did. It's my precious.

Carrie - What brand is your fridge and how wide is it? I'm open to exploring alternatives to a honking big fridge. (Though during the pandemic our big sub zero has been phenomenal for storing huge orders of meat, fish, soups, and sauces.) There are only two of us in our household so on a regular basis we could do with a smaller fridge, but we do have large dinner parties and my parents stay for a week at a time and I can see a smaller fridge being challenging for that. IloveMod - Yep, you are right, it is a trick of the lens. The great thing about integrated fridges is that they have some kind of hinge component that allows them to open very wide without needing the clearance you are talking about. So the door could be flush with the wall and open wide. I may have just explained to myself another advantage of an integrated vs a counter depth!