Black matches, so it reduces one Black mana
It's more money upfront, but you'll likely save money just getting the card straight up
It's strong everywhere, but it has enhanced value in archetypes that care about counters generally, +1/+1 counters specifically, proliferate tricks for multicolor brews looking to add loyalty counters for their planeswalkers, four and five-color decks, Commanders with evasion, Commanders with a power that, when increased by 1 get a faster kill, Equipment, Aura, and Voltron decks looking to get in kills with their Commander, and loads more
Any "as [this creature] enters" or "[this creature] enters with" abilities of the copied creature will also work.