I have a John Boos mobile butcher block island (30.75 inches wide x 20 inches deep - stands 35 3/8" tall). It has 4 locking casters, with drawer + (1) 10" drop leaf, model "CUCE" CUCINA ELEGANTE - MAPLE TOP.
My kitchen is a small square. A regular island would interfere with the oven door, dishwasher door, and opening drawers; a moving island can get out of the way.
Interestingly, I rarely lock the casters, having learned how to place hot dishes or groceries on the top without causing the island to move.
When my friend comes over with a contribution for dinner, I lock the casters so she can use it (It confuses her otherwise).
The butcher block island wasn't cheap. But nothing else would work as well.
https://www.johnboos.com/collections/islands
P.S. Because it's so lovely, I haven't yet started using it as a butcher block; I bring a cutting board to it!
(I bought it in 2021)
Edited again to add a "close" look alike
Mine has only one drop leaf.
