Don't fall for the idea that microcement can supposedly be applied over old tiles or a poorly prepared surface. That's a common mistake that leads right to the problems you're worried about. The surface needs to be perfectly clean, degreased, and often requires priming. If you skip that, then yeah, it'll crack and peel, and redoing it later costs more than doing it right the first time.
As for practicality: it's easy to clean, just don't use aggressive acidic cleaners. Microcement gets duller over time, which is actually a plus - stains and fingerprints show less than on shiny tiles. But small damage is more visible, and if something gets scratched, you'll notice it. Sealing with a top coat is a mandatory part of the process, not an option.
Money-wise, it's more expensive than regular tiles, especially when you factor in labor costs, because it's a technical process, not just tiling work. But you get a seamless coating without grout lines, and it really does look different. If your budget allows and you're ready to work with a good specialist, then it's worth the money. If you're looking to save and get it done "quick," microcement isn't your option.