Polished concrete is NOT the same as SEALED concrete. All concrete floors have maintenance. The LOWEST COST concrete floors (ie polished WITHOUT sealant) have the HIGHEST amount of maintenance. The HIGHEST PRICED concrete floors (3-5 stains + clear epoxy finish) have MINOR MAINTENANCE (aka. sweeping and mopping). The thing you need to be 100% aware of: concrete STAINS and ETCHES! These issues do NOT go away until you work with the EXPENSIVE epoxy finishes. So... a low-priced polished concrete WILL STAIN (ketchup, oils, mustard, red wine, etc) and they will ETCH (reduction of gloss due to harsh acids or alkaline products such as lemon juice or ammonia cleaners). Polished concrete can be MORE DELICATE than marble. And marble takes a tremendous amount of effort to keep looking good. Both marble and polished concrete require FREQUENT sealing (3-4 times per year; every year for many years until it is saturated with the sealant). The sealants do NOT stop the etching. Etching will continue for as long as you own the floor. And if you decide to use a sealant, you may have to POLISH the floor every 6 months as well. Whew. For such a "tough floor", concrete certainly takes a LOT of effort. If you want concrete, you MUST go into this with your EYES OPEN. If you want "bullet proof" floors that have ZERO maintenance = porcelain tile. If you want bullet proof CONCRETE FLOORS then you need to pay $$$$ money to get the high-end epoxy finish.

Sigh...That is such a personal decision. You obviously love the tile so here's my opinion. Appearance, I'm not overly impressed with the porcelain tiles made to look like polished marble. I prefer the matte of your two finishes. I live in the southern states, so hard surfaces such as tile are increasing greatly. As far as practicality with kids, I don't see a problem at all. Just keep your floors clean, clean up spills as soon as possible if/when they occur and have them professionally cleaned as needed and they will provide years of enjoyment.

Yup - that's the same one I recommend.

The use of polished porcelain tile in showers is extremely common. That's almost all you see in fact. Some people like a matte finish - it's just a matter of preference. Porcelain tile is extremely durable and the shine does not wear off unless you deliberately try to dull it with some very caustic chemicals. It does not become dull under normal use. To be 100% sure about what you're buying, ask the vendor about the characteristics of the product you're interested in. Anything with a handpainted design could be less durable.