In my experience, it is almost always worth it to pay a few dollars extra for booster boxes to support your local gaming store
Ishai, Ojutai Dragonspeaker, just like Vial Smasher the Fierce, gets some of its value out of being a Partner Commander
Its good at helping you ramp if you have ways to keep reactivating its ability
And then theres Teysa Karlov, which will let a dies trigger happen again, though you might want to include an element of token creatures in the deck to get her full benefit
The value of X is determined only once, as Dimir Strandcatcher's second ability resolves
One of the rarest Pokmon cards of all time, Pikachu Illustrator, has gone under the hammer for close to a cool half a million dollars