Built a house for some folks that wanted to do that. They were gonna handle it themselves. As I finished my part they were starting. Year or so later I returned to do something. They had gave up on it and installed standard flooring. Said there didn't like it.

We built 11 years ago & went with stained concrete. Did it myself for around $600. We have area rugs in the dining room, living room, and the kids' rooms. I've re-waxed it twice. We went with "COLA" color and it has almost a marbled finish to it.

Yes, it has a few cracks. They are small and, in my opinion, give some character to the house. I like them.

My brother in law built at the same time we did. He too went with stained floors, but we scored his in 2' x 2' squares. His cracks tend to run the scored lines and are less visible, but the scores make it more difficult to keep the floor clean (like tile).

Folks in Vestavia may not have bought them, but there are a bunch of high-end homes in Mobile with nicely stained floors.

Also, if you decide you don't like it, you can cover it up with something else and not be out much.

Ours was an acid stain. Used a pump sprayer, sprayed it on as evenly as possible, rinsed off with hose. Want it darker? Do it again. You just keep reapplying till it is as dark as you want it. Wax/seal the piss out of it when you are done and it's a wrap.

Warnings: a plumber and glue can screw your world up. If you go the stain route, do it during the framing phase of construction. Then, cover your floors with felt paper until sheet rock & painting is done.

Also, rust marks from nails, saw blades etc are easily sanded/ground out prior to staining and sealing.

carpet in bedrooms and ceramic tile throughout the rest of the house. keeps it cooler in the summer, but you gotta wear sock in the winter.

We hired our floors done. We kept them covered the entire time during construction. The stain guys came in and put this sticky plastic over all our walls, cabinets, everything. They sprayed the floors with acid to etch them, then put on the stain, and then put on a polyurethane clear coat. We have been in our house almost 2 years. Like I said earlier, there are imperfections everywhere in our slab. Cracks, leaf marks, chips, and the stain really shows those imperfections. To some people it would really bother them. I like it and so does my wife. We went with what the call the "cowboy" color stain. They are very easy to keep clean.

Correct and they are also painting bricks

I've seen painted brick for years, never concrete floors in a house. I've spent my working life in heavy manufacturing on concrete, don't want it in my house. My brain would tell my knees to start hurting.

Pretty much this.

It's cheap to stain it, but make sure it's planned from the beginning and the finisher knows what they are doing. You want a smooth, slick surface. Make sure you stay on top of the builder to keep the floors covered before you stain. Any kind of chemical residue will leave marks like the saw blade mentioned in Gomer's post.
I loved the stained floors we had in our previous house. Easy to clean and looked good. We had the cola stain color. Wet mop and it shines as good as any wood floor or tile.
I'd do the whole house. If you wind up not liking it, you do have to move your molding and door bottoms up to put tile or carpet in, but that's the only issue I can think of.
It's gonna crack when the house settles. You can minimize settling by doing your dirt work a couples months before building, and riding a heavy dozer over it to pack it good, then letting the rain pack it. There will still be some settling cracks though.

Hardwood in foyer, Carpet in living-room and bedrooms, ceramic tile in bathrooms and kitchen. Had vinyl in kitchen but it starts to look terrible after several years. Vinyl gets cuts and yellows over time.

I have never understood why anybody would paint bricks.

I never understood why anyone would want brick any color but red or some variance of red. And I don't mean painted red.

I hate red brick lol we just have the foundation in brick but it's a white wash brown color..i do like a couple variants of red