Pro mode is worth the effort in eventual real practical skill

Once you have the basics down, I recommend the Practice mode for each song you want to learn.

About the gameplay: Having played Rock Band since 1 and Guitar Hero before that, regular keys mode is a breeze.

After you get accustomed to the very very basic of things you can move on to the learn a song mode (Only available for songs from Harmonix not RBN

I've had Rock Band 3 for a few months and decided to pick up one of these keyboards to try out the "Pro Keys" feature, and see just how fun the pro modes are

The other mode is not as fun.

The pro mode intrigued me enough to pick it up later

the pro mode is challenging and it works great the only thing you'll prolly need is a stand for it.

Pro mode on the other hand is VERY difficult.

Even though this mode is tough, it is very satisfying - once you get used to things, you'll really feel like you're playing some rock and roll keyboards

I should mention that the Rockband 3 songs let you play the keyboard in either "normal mode" (five colours) or "pro keys mode" (proper keyboard notes, with black and white keys) mode

This mode is TOUGH, but there are some decent tutorials available in order to give you some basis to work from

Now my pride and joy in my rock band 3 set ;D