[clentaminator]

> Piano is easier

In terms of barrier-to-entry, I'd agree. There's a greater requirement for dexterity in the left hand (assuming traditional layout) to get a good, consistent tone from the instrument, and much more "up front" difficulty in learning.

As experience grows, however, piano opens up a wealth of incredibly challenging literature, for example Bach's Overture in the French Style, Ravel's Gaspard de la Nuit, and Balakirev's Islamey.

So the "progression curves" of the two instruments, for want of a better phrase, are very different, and certainly look like they favour piano for ease-of-entry.